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Xorg Unable To Find fbdev #1

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nomadlogic opened this issue May 25, 2016 · 0 comments
Closed

Xorg Unable To Find fbdev #1

nomadlogic opened this issue May 25, 2016 · 0 comments

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@nomadlogic
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CPU/GPU: Intel® HD Graphics 4400

I am able to boot via the May-24 CFT disk image. Primary laptop display is unreadable. But I am able to log in as root, kldload drm2 and once i load the i915kms module the display resets and I am able to see text with out issue.

I then attempt to start X which fails with the following error:
619.959 LoadModule: "fbdev"
619.960 Warning, couldn't open module fbdev
619.960 UnloadModule: "fbdev"
619.960 Unloading fbdev
619.960 Failed to load module "fbdev" (module does not exist, 0)

I've attached the full output of Xorg.0.log from this system for further analysis. I have also attached the full /var/log/messages file which contains some debug output from drivers loading etc.

Xorg.0.log.txt
messages.txt

I also was able to generate a kernel panic on this configuration but it looks unusable, so that may be an unrelated bug.

mattmacy pushed a commit that referenced this issue Jun 24, 2016
Drop scan generation number and node table scan lock - the only place
where ni_scangen is checked is in ieee80211_timeout_stations() (and it
is used to prevent duplicate checking of the same node); node scan lock
protects only this variable + node table scan generation number.

This will fix (at least) next LOR (hostap mode):

lock order reversal:
1st 0xc175f84c urtwm0_scan_loc (urtwm0_scan_loc) @ /usr/src/sys/modules/wlan/../../net80211/ieee80211_node.c:2019
2nd 0xc175e018 urtwm0_com_lock (urtwm0_com_lock) @ /usr/src/sys/modules/wlan/../../net80211/ieee80211_node.c:2693
stack backtrace:
#0 0xa070d1c5 at witness_debugger+0x75
#1 0xa070d0f6 at witness_checkorder+0xd46
#2 0xa0694cce at __mtx_lock_flags+0x9e
#3 0xb03ad9ef at ieee80211_node_leave+0x12f
#4 0xb03afd13 at ieee80211_timeout_stations+0x483
#5 0xb03aa1c2 at ieee80211_node_timeout+0x42
#6 0xa06c6fa1 at softclock_call_cc+0x1e1
#7 0xa06c7518 at softclock+0xc8
#8 0xa06789ae at intr_event_execute_handlers+0x8e
#9 0xa0678fa0 at ithread_loop+0x90
#10 0xa0675fbe at fork_exit+0x7e
#11 0xa08af910 at fork_trampoline+0x8

In addition to the above:

* switch to ieee80211_iterate_nodes();
* do not assert that node table lock is held, while calling node_age();
  that's not really needed (there are no resources, which can be protected
  by this lock) + this fixes LOR/deadlock between ieee80211_timeout_stations()
  and ieee80211_set_tim() (easy to reproduce in HOSTAP mode while
  sending something to an STA with enabled power management).

Tested:

* (avos) urtwn0, hostap mode
* (adrian) AR9380, STA mode
* (adrian) AR9380, AR9331, AR9580, hostap mode

Notes:

* This changes the net80211 internals, so you have to recompile all of it
  and the wifi drivers.

Submitted by:	avos
Approved by:	re (delphij)
Differential Revision:	https://reviews.freebsd.org/D6833
mattmacy pushed a commit that referenced this issue Aug 9, 2016
commit e2c8b8701e2d moved modeset locking inside resume/suspend
functions, but missed a code path only executed on lid close/open
on older hardware. The result was a deadlock when closing and
opening the lid without suspending on such hardware:

 =============================================
 [ INFO: possible recursive locking detected ]
 4.6.0-rc1 #385 Not tainted
 ---------------------------------------------
 kworker/0:3/88 is trying to acquire lock:
  (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa063e6a4>] intel_display_resume+0x4a/0x12f [i915]

 but task is already holding lock:
  (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa02d0d4f>] drm_modeset_lock_all+0x3e/0xa6 [drm]

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&dev->mode_config.mutex);
   lock(&dev->mode_config.mutex);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 7 locks held by kworker/0:3/88:
  #0:  ("kacpi_notify"){++++.+}, at: [<ffffffff81068dfc>] process_one_work+0x14a/0x50b
  #1:  ((&dpc->work)#2){+.+.+.}, at: [<ffffffff81068dfc>] process_one_work+0x14a/0x50b
  #2:  ((acpi_lid_notifier).rwsem){++++.+}, at: [<ffffffff8106f874>] __blocking_notifier_call_chain+0x34/0x65
  #3:  (&dev_priv->modeset_restore_lock){+.+.+.}, at: [<ffffffffa0664cf6>] intel_lid_notify+0x3c/0xd9 [i915]
  #4:  (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa02d0d4f>] drm_modeset_lock_all+0x3e/0xa6 [drm]
  #5:  (crtc_ww_class_acquire){+.+.+.}, at: [<ffffffffa02d0d59>] drm_modeset_lock_all+0x48/0xa6 [drm]
  #6:  (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffa02d0b2a>] modeset_lock+0x13c/0x1cd [drm]

 stack backtrace:
 CPU: 0 PID: 88 Comm: kworker/0:3 Not tainted 4.6.0-rc1 #385
 Hardware name: LENOVO 2776LEG/2776LEG, BIOS 6EET55WW (3.15 ) 12/19/2011
 Workqueue: kacpi_notify acpi_os_execute_deferred
  0000000000000000 ffff88022fd5f990 ffffffff8124af06 ffffffff825b39c0
  ffffffff825b39c0 ffff88022fd5fa60 ffffffff8108f547 ffff88022fd5fa70
  000000008108e817 ffff880230236cc0 0000000000000000 ffffffff825b39c0
 Call Trace:
  [<ffffffff8124af06>] dump_stack+0x67/0x90
  [<ffffffff8108f547>] __lock_acquire+0xdb5/0xf71
  [<ffffffff8108bd2c>] ? look_up_lock_class+0xbe/0x10a
  [<ffffffff8108fae2>] lock_acquire+0x137/0x1cb
  [<ffffffff8108fae2>] ? lock_acquire+0x137/0x1cb
  [<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915]
  [<ffffffff8148202f>] mutex_lock_nested+0x7e/0x3a4
  [<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915]
  [<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915]
  [<ffffffffa02d0b2a>] ? modeset_lock+0x13c/0x1cd [drm]
  [<ffffffffa063e6a4>] intel_display_resume+0x4a/0x12f [i915]
  [<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915]
  [<ffffffffa02d0b2a>] ? modeset_lock+0x13c/0x1cd [drm]
  [<ffffffffa02d0b2a>] ? modeset_lock+0x13c/0x1cd [drm]
  [<ffffffffa02d0bf7>] ? drm_modeset_lock+0x17/0x24 [drm]
  [<ffffffffa02d0c8b>] ? drm_modeset_lock_all_ctx+0x87/0xa1 [drm]
  [<ffffffffa0664d6a>] intel_lid_notify+0xb0/0xd9 [i915]
  [<ffffffff8106f4c6>] notifier_call_chain+0x4a/0x6c
  [<ffffffff8106f88d>] __blocking_notifier_call_chain+0x4d/0x65
  [<ffffffff8106f8b9>] blocking_notifier_call_chain+0x14/0x16
  [<ffffffffa0011215>] acpi_lid_send_state+0x83/0xad [button]
  [<ffffffffa00112a6>] acpi_button_notify+0x41/0x132 [button]
  [<ffffffff812b07df>] acpi_device_notify+0x19/0x1b
  [<ffffffff812c8570>] acpi_ev_notify_dispatch+0x49/0x64
  [<ffffffff812ab9fb>] acpi_os_execute_deferred+0x14/0x20
  [<ffffffff81068f17>] process_one_work+0x265/0x50b
  [<ffffffff810696f5>] worker_thread+0x1fc/0x2dd
  [<ffffffff810694f9>] ? rescuer_thread+0x309/0x309
  [<ffffffff810694f9>] ? rescuer_thread+0x309/0x309
  [<ffffffff8106e2d6>] kthread+0xe0/0xe8
  [<ffffffff8107bc47>] ? local_clock+0x19/0x22
  [<ffffffff81484f42>] ret_from_fork+0x22/0x40
  [<ffffffff8106e1f6>] ? kthread_create_on_node+0x1b5/0x1b5

Fixes: e2c8b8701e2d ("drm/i915: Use atomic helpers for suspend, v2.")
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1459328913-13719-1-git-send-email-bjorn@mork.no
mattmacy pushed a commit that referenced this issue Aug 11, 2016
intel_pipe_will_have_type() doesn't just look at the passied in
pipe_config, instead it expects there to be a full atomic state behind
it. Obviously that won't go so well when vlv_force_pll_on() just uses a
temp pipe_config. Fix things by using pipe_config->has_dsi_encoder
instead intel_pipe_will_have_type(INTEL_OUTPUT_DSI) to check if we need
to actually enable the DPLL.

Here's an example oops for reference:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
IP: [<ffffffffa0389a5b>] intel_pipe_will_have_type+0x15/0x7b [i915]
PGD 7acda067 PUD 72696067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
Modules linked in: i915 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm intel_gtt agpgart netconsole psmouse atkbd iTCO_wdt libps2 coretemp hwmon efi_pstore intel_rapl punit_atom_debug efivars pcspkr i2c_i801 r8169 lpc_ich mii processor_thermal_device snd_soc_rt5670 intel_soc_dts_iosf snd_soc_rl6231 i2c_hid hid snd_intel_sst_acpi snd_intel_sst_core snd_soc_sst_mfld_platform snd_soc_sst_match snd_soc_core i8042 serio snd_compress snd_pcm snd_timer snd i2c_designware_platform sdhci_acpi i2c_designware_core soundcore sdhci pwm_lpss_platform mmc_core pwm_lpss spi_pxa2xx_platform evdev int3403_thermal int3400_thermal int340x_thermal_zone acpi_thermal_rel sch_fq_codel ip_tables x_tables ipv6 autofs4
CPU: 3 PID: 290 Comm: Xorg Tainted: G     U          4.6.0-rc4-bsw+ #2876
Hardware name: Intel Corporation CHERRYVIEW C0 PLATFORM/Braswell CRB, BIOS BRAS.X64.X088.R00.1510270350 10/27/2015
task: ffff88007a8dd200 ti: ffff880173ac4000 task.ti: ffff880173ac4000
RIP: 0010:[<ffffffffa0389a5b>]  [<ffffffffa0389a5b>] intel_pipe_will_have_type+0x15/0x7b [i915]
RSP: 0018:ffff880173ac7928  EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff880176594000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000009 RDI: ffff880176594000
RBP: ffff880173ac7930 R08: 0000000000019290 R09: 0000000000000000
R10: ffff880173ac7890 R11: 00000000000080cf R12: ffff88017fbd4000
R13: ffffffffa03e3c44 R14: ffff88007492c000 R15: ffff88007492c000
FS:  00007ff8936a6940(0000) GS:ffff88017ef80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000030 CR3: 0000000177e08000 CR4: 00000000001006e0
Stack:
 ffff880176594000 ffff880173ac7948 ffffffffa0389b42 ffff880176594000
 ffff880173ac7978 ffffffffa0396e02 ffff8801765b0000 ffff88007af660d8
 0000000000000000 0000000000000004 ffff880173ac79c0 ffffffffa03b6b64
Call Trace:
 [<ffffffffa0389b42>] chv_compute_dpll.isra.39+0x33/0x55 [i915]
 [<ffffffffa0396e02>] vlv_force_pll_on+0x80/0xc6 [i915]
 [<ffffffffa03b6b64>] vlv_power_sequencer_pipe+0x29b/0x3dd [i915]
 [<ffffffffa03b6cd4>] _pp_stat_reg+0x2e/0x38 [i915]
 [<ffffffffa03b6dc1>] wait_panel_status+0x4c/0x1ec [i915]
 [<ffffffffa03b6fcb>] wait_panel_power_cycle+0x6a/0xb4 [i915]
 [<ffffffffa03b70da>] edp_panel_vdd_on+0xc5/0x1d1 [i915]
 [<ffffffffa03b861b>] intel_dp_aux_ch+0x55/0x572 [i915]
 [<ffffffff810af5c8>] ? mark_held_locks+0x5d/0x74
 [<ffffffff81518e61>] ? mutex_lock_nested+0x321/0x346
 [<ffffffff81094007>] ? preempt_count_sub+0xf2/0x102
 [<ffffffffa03b8cb4>] intel_dp_aux_transfer+0x17c/0x1b5 [i915]
 [<ffffffffa03028ef>] drm_dp_dpcd_access+0x62/0xed [drm_kms_helper]
 [<ffffffffa0302995>] drm_dp_dpcd_read+0x1b/0x1f [drm_kms_helper]
 [<ffffffffa03b5147>] intel_dp_dpcd_read_wake+0x31/0x69 [i915]
 [<ffffffffa03bb36a>] intel_dp_long_pulse+0x15f/0x5ed [i915]
 [<ffffffffa03bbb09>] intel_dp_detect+0x79/0x95 [i915]
 [<ffffffffa030340e>] drm_helper_probe_single_connector_modes+0xc7/0x3db [drm_kms_helper]
 [<ffffffffa029de23>] drm_mode_getconnector+0xe9/0x333 [drm]
 [<ffffffff810b1cfb>] ? lock_acquire+0x137/0x1df
 [<ffffffffa0292364>] drm_ioctl+0x266/0x3ae [drm]
 [<ffffffffa029dd3a>] ? drm_mode_getcrtc+0x126/0x126 [drm]
 [<ffffffff811af082>] vfs_ioctl+0x18/0x34
 [<ffffffff811af682>] do_vfs_ioctl+0x547/0x5fe
 [<ffffffff811b9acb>] ? __fget_light+0x62/0x71
 [<ffffffff811af77c>] SyS_ioctl+0x43/0x61
 [<ffffffff81001a82>] do_syscall_64+0x63/0xf8
 [<ffffffff8151bc9a>] entry_SYSCALL64_slow_path+0x25/0x25
Code: 35 00 40 a0 e8 97 4b ce e0 b8 17 00 00 00 5d c3 b8 17 00 00 00 c3 0f 1f 44 00 00 55 31 c0 31 d2 48 89 e5 53 48 8b 8f e8 01 00 00 <44> 8b 49 30 41 39 c1 7e 2d 4c 8b 51 38 4c 8b 41 40 49 83 3c c2
RIP  [<ffffffffa0389a5b>] intel_pipe_will_have_type+0x15/0x7b [i915]
 RSP <ffff880173ac7928>
CR2: 0000000000000030

The regressing patch wasn't exactly new (as in first posted more than
six months ago), so I'm a bit baffled how I didn't manage to hit this
myself so far.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Marius Vlad <marius.c.vlad@intel.com>
Reported-by: Marius Vlad <marius.c.vlad@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=94995
Fixes: cd2d34d9b61f ("drm/i915: Setup DPLL/DPLLMD for DSI too on VLV/CHV")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1461000844-20543-1-git-send-email-ville.syrjala@linux.intel.com
Tested-by: Marius Vlad <marius.c.vlad@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
mattmacy pushed a commit that referenced this issue Aug 12, 2016
When I was writing an atomic wrapper for rmfb, I ran into the
following backtrace from lockdep:

=============================================
[ INFO: possible recursive locking detected ]
4.5.0-patser+ #4696 Tainted: G     U
---------------------------------------------
kworker/2:2/2608 is trying to acquire lock:
 (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c9ddc>] drm_modeset_lock+0x7c/0x120 [drm]

but task is already holding lock:
 (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c98cd>] modeset_backoff+0x8d/0x220 [drm]

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(crtc_ww_class_mutex);
  lock(crtc_ww_class_mutex);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

4 locks held by kworker/2:2/2608:
 #0:  ("events"){.+.+.+}, at: [<ffffffff810a5eea>] process_one_work+0x15a/0x6c0
 #1:  ((&arg.work)){+.+.+.}, at: [<ffffffff810a5eea>] process_one_work+0x15a/0x6c0
 #2:  (crtc_ww_class_acquire){+.+.+.}, at: [<ffffffffc004532a>] drm_atomic_helper_remove_fb+0x4a/0x1d0 [drm_kms_helper]
 #3:  (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c98cd>] modeset_backoff+0x8d/0x220 [drm]

While lockdep probably catches this bug when it happens, it's better
to explicitly warn when state->acquire_ctx is not set.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1462266751-29123-1-git-send-email-maarten.lankhorst@linux.intel.com
mattmacy pushed a commit that referenced this issue Aug 12, 2016
Retriving the horizontal timings from the port registers as part of
get_config().

This fixes a division by zero:

[   56.916557] divide error: 0000 [#1] PREEMPT SMP
[   56.921741] Modules linked in: i915(+) drm_kms_helper syscopyarea
sysfillrect sysimgblt fb_sys_fops drm intel_gtt agpgart cf
g80211 rfkill binfmt_misc ax88179_178a kvm_intel kvm irqbypass crc32c_intel
efivars tpm_tis tpm fuse
[   56.944106] CPU: 3 PID: 1097 Comm: modprobe Not tainted 4.6.0-rc4+ #433
[   56.951501] Hardware name: Intel Corp. Broxton M/RVP, BIOS
BXT1RVPA.X64.0131.B30.1604142217 04/14/2016
[   56.961908] task: ffff88007a854d00 ti: ffff88007aea0000 task.ti:
ffff88007aea0000
[   56.970273] RIP: 0010:[<ffffffffa01235b2>]  [<ffffffffa01235b2>]
drm_mode_hsync+0x22/0x40 [drm]
[   56.980043] RSP: 0018:ffff88007aea3788  EFLAGS: 00010206
[   56.985982] RAX: 000000000788b600 RBX: ffff880073c22108 RCX:
0000000000000000
[   56.993957] RDX: 0000000000000000 RSI: ffff88007ab06800 RDI:
ffff880073c22108
[   57.001935] RBP: ffff88007aea3788 R08: 0000000000000001 R09:
ffff880073c221e8
[   57.009903] R10: ffff880073c22108 R11: 0000000000000001 R12:
ffff88007a300000
[   57.017872] R13: ffff880073c22000 R14: ffff880175f78000 R15:
ffff880175f78798
[   57.025849] FS:  00007f105d3e6700(0000) GS:ffff88017fd80000(0000)
knlGS:0000000000000000
[   57.034894] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   57.041317] CR2: 00007f4d485101d0 CR3: 000000007a820000 CR4:
00000000003406e0
[   57.049292] Stack:
[   57.051539]  ffff88007aea37a0 ffffffffa043b632 ffff880175f787c8
ffff88007aea3810
[   57.059825]  ffffffffa043d59e ffff880175f787b0 ffff88007ab68c00
ffff88007aea37f0
[   57.068128]  ffff880073c221e8 ffff880073c22108 ffff880175f78780
ffff880100000000
[   57.076430] Call Trace:
[   57.079254]  [<ffffffffa043b632>] intel_mode_from_pipe_config+0x82/0xb0
[i915]
[   57.087405]  [<ffffffffa043d59e>] intel_modeset_setup_hw_state+0x55e/0xd60
[i915]
[   57.095847]  [<ffffffffa043ff94>] intel_modeset_init+0x8e4/0x1630 [i915]
[   57.103415]  [<ffffffffa047bcf0>] i915_driver_load+0xbe0/0x1980 [i915]
[   57.110745]  [<ffffffffa0116c19>] drm_dev_register+0xa9/0xc0 [drm]
[   57.117681]  [<ffffffffa011921d>] drm_get_pci_dev+0x8d/0x1e0 [drm]
[   57.124600]  [<ffffffff8195f942>] ? _raw_spin_unlock_irqrestore+0x42/0x70
[   57.132253]  [<ffffffffa03b0384>] i915_pci_probe+0x34/0x50 [i915]
[   57.139070]  [<ffffffff8149c375>] local_pci_probe+0x45/0xa0
[   57.145303]  [<ffffffff8149d300>] ? pci_match_device+0xe0/0x110
[   57.151924]  [<ffffffff8149d6cb>] pci_device_probe+0xdb/0x130
[   57.158355]  [<ffffffff81579b93>] driver_probe_device+0x223/0x440
[   57.165169]  [<ffffffff81579e85>] __driver_attach+0xd5/0x100
[   57.171500]  [<ffffffff81579db0>] ? driver_probe_device+0x440/0x440
[   57.178510]  [<ffffffff81577736>] bus_for_each_dev+0x66/0xa0
[   57.184841]  [<ffffffff815793de>] driver_attach+0x1e/0x20
[   57.190881]  [<ffffffff81578d6e>] bus_add_driver+0x1ee/0x280
[   57.197212]  [<ffffffff8157abc0>] driver_register+0x60/0xe0
[   57.203447]  [<ffffffff8149bc50>] __pci_register_driver+0x60/0x70
[   57.210285]  [<ffffffffa0119450>] drm_pci_init+0xe0/0x110 [drm]
[   57.216911]  [<ffffffff810dcd8d>] ? trace_hardirqs_on+0xd/0x10
[   57.223434]  [<ffffffffa023a000>] ? 0xffffffffa023a000
[   57.229237]  [<ffffffffa023a092>] i915_init+0x92/0x99 [i915]
[   57.235570]  [<ffffffff810003db>] do_one_initcall+0xab/0x1d0
[   57.241900]  [<ffffffff810f9eef>] ? rcu_read_lock_sched_held+0x7f/0x90
[   57.249205]  [<ffffffff81204f18>] ? kmem_cache_alloc_trace+0x248/0x2b0
[   57.256509]  [<ffffffff811a5eee>] ? do_init_module+0x27/0x1d9
[   57.262934]  [<ffffffff811a5f26>] do_init_module+0x5f/0x1d9
[   57.269167]  [<ffffffff8112392f>] load_module+0x20ef/0x27b0
[   57.275401]  [<ffffffff8111f8e0>] ? store_uevent+0x40/0x40
[   57.281541]  [<ffffffff81124243>] SYSC_finit_module+0xc3/0xf0
[   57.287969]  [<ffffffff8112428e>] SyS_finit_module+0xe/0x10
[   57.294203]  [<ffffffff81960069>] entry_SYSCALL_64_fastpath+0x1c/0xac
[   57.301406] Code: ff 5d c3 66 0f 1f 44 00 00 0f 1f 44 00 00 8b 87 d8 00 00
00 55 48 89 e5 85 c0 75 22 8b 4f 68 85 c9 78 1b 69 47 58 e8 03 00 00 99 <f7> f9
b9 d3 4d 62 10 05 f4 01 00 00 f7 e1 89 d0 c1 e8 06 5d c3
[   57.322964] RIP  [<ffffffffa01235b2>] drm_mode_hsync+0x22/0x40 [drm]
[   57.330103]  RSP <ffff88007aea3788>
[   57.334276] ---[ end trace d414224cb2e2a4cf ]---
[   57.339861] modprobe (1097) used greatest stack depth: 12048 bytes left

Fixes: 6f0e7535e7e1 ("drm/i915/BXT: Get pipe conf from the port registers")
Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1461053894-5058-1-git-send-email-ramalingam.c@intel.com
(cherry picked from commit cefc4e18785123326c5d4d985085e32160fef7f5)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
mattmacy pushed a commit that referenced this issue Aug 12, 2016
In commit f9476a6c6d0c ("drm/i915: Refactor platform specifics out of
intel_get_shared_dpll()"), the ibx_get_dpll() function lacked an error
check, that can lead to a NULL pointer dereference when trying to enable
three pipes.

BUG: unable to handle kernel NULL pointer dereference at 0000000000000068
IP: [<ffffffffa0482275>] intel_reference_shared_dpll+0x15/0x100 [i915]
PGD cec87067 PUD d30ce067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
Modules linked in: snd_hda_intel i915 drm_kms_helper drm intel_gtt sch_fq_codel cfg80211 binfmt_misc i2c_algo_bit cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea intel_rapl iosf_mbi x86_pkg_temp_thermal coretemp agpgart kvm_intel snd_hda_codec_hdmi kvm iTCO_wdt snd_hda_codec_realtek snd_hda_codec_generic irqbypass aesni_intel aes_x86_64 glue_helper lrw gf128mul ablk_helper cryptd psmouse pcspkr snd_hda_codec i2c_i801 snd_hwdep snd_hda_core snd_pcm snd_timer lpc_ich mfd_core snd soundcore wmi evdev tpm_tis tpm [last unloaded: drm]
CPU: 3 PID: 5810 Comm: kms_flip Tainted: G     U  W       4.6.0-test+ #3
Hardware name:                  /DZ77BH-55K, BIOS BHZ7710H.86A.0100.2013.0517.0942 05/17/2013
task: ffff8800d3908040 ti: ffff8801166c8000 task.ti: ffff8801166c8000
RIP: 0010:[<ffffffffa0482275>]  [<ffffffffa0482275>] intel_reference_shared_dpll+0x15/0x100 [i915]
RSP: 0018:ffff8801166cba60  EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000001 RSI: ffff8800d07f1bf8 RDI: 0000000000000000
RBP: ffff8801166cba88 R08: 0000000000000002 R09: ffff8800d32e5698
R10: 0000000000000001 R11: ffff8800cc89ac88 R12: ffff8800d07f1bf8
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f4c3fc8d8c0(0000) GS:ffff88011bcc0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000068 CR3: 00000000d3b4c000 CR4: 00000000001406e0
Stack:
 0000000000000000 ffff8800d07f1bf8 0000000000000000 ffff8800d04c0000
 0000000000000000 ffff8801166cbaa8 ffffffffa04823a7 ffff8800d07f1bf8
 ffff8800d32e5698 ffff8801166cbab8 ffffffffa04840cf ffff8801166cbaf0
Call Trace:
 [<ffffffffa04823a7>] ibx_get_dpll+0x47/0xa0 [i915]
 [<ffffffffa04840cf>] intel_get_shared_dpll+0x1f/0x50 [i915]
 [<ffffffffa046d080>] ironlake_crtc_compute_clock+0x280/0x430 [i915]
 [<ffffffffa0472ac0>] intel_crtc_atomic_check+0x240/0x320 [i915]
 [<ffffffffa03da18e>] drm_atomic_helper_check_planes+0x14e/0x1d0 [drm_kms_helper]
 [<ffffffffa0474a0c>] intel_atomic_check+0x5dc/0x1110 [i915]
 [<ffffffffa029d3aa>] drm_atomic_check_only+0x14a/0x660 [drm]
 [<ffffffffa029d086>] ? drm_atomic_set_crtc_for_connector+0x96/0x100 [drm]
 [<ffffffffa029d8d7>] drm_atomic_commit+0x17/0x60 [drm]
 [<ffffffffa03dc3b7>] restore_fbdev_mode+0x237/0x260 [drm_kms_helper]
 [<ffffffffa029c65a>] ? drm_modeset_lock_all_ctx+0x9a/0xb0 [drm]
 [<ffffffffa03de9b3>] drm_fb_helper_restore_fbdev_mode_unlocked+0x33/0x80 [drm_kms_helper]
 [<ffffffffa03dea2d>] drm_fb_helper_set_par+0x2d/0x50 [drm_kms_helper]
 [<ffffffffa03de93a>] drm_fb_helper_hotplug_event+0xaa/0xf0 [drm_kms_helper]
 [<ffffffffa03de9d6>] drm_fb_helper_restore_fbdev_mode_unlocked+0x56/0x80 [drm_kms_helper]
 [<ffffffffa0490f72>] intel_fbdev_restore_mode+0x22/0x80 [i915]
 [<ffffffffa04ba45e>] i915_driver_lastclose+0xe/0x20 [i915]
 [<ffffffffa02810de>] drm_lastclose+0x2e/0x130 [drm]
 [<ffffffffa028148c>] drm_release+0x2ac/0x4b0 [drm]
 [<ffffffff811a6b2d>] __fput+0xed/0x1f0
 [<ffffffff811a6c6e>] ____fput+0xe/0x10
 [<ffffffff81079156>] task_work_run+0x76/0xb0
 [<ffffffff8105aaab>] do_exit+0x3ab/0xc60
 [<ffffffff810a145f>] ? trace_hardirqs_on_caller+0x12f/0x1c0
 [<ffffffff8105c67e>] do_group_exit+0x4e/0xc0
 [<ffffffff8105c704>] SyS_exit_group+0x14/0x20
 [<ffffffff8158bb25>] entry_SYSCALL_64_fastpath+0x18/0xa8
Code: 14 80 48 8d 34 90 b8 01 00 00 00 d3 e0 09 04 b3 5b 41 5c 5d c3 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 49 89 fe 41 55 41 54 53 <44> 8b 67 68 48 89 f3 48 8b be 08 02 00 00 4c 8b 2e e8 15 9d fd
RIP  [<ffffffffa0482275>] intel_reference_shared_dpll+0x15/0x100 [i915]
 RSP <ffff8801166cba60>
CR2: 0000000000000068

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Fixes: f9476a6c6d0c ("drm/i915: Refactor platform specifics out of intel_get_shared_dpll()")
Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1463748426-5956-1-git-send-email-ander.conselvan.de.oliveira@intel.com
(cherry picked from commit bb143165510661feda06fd99298b8b3a94af3046)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
mattmacy pushed a commit that referenced this issue Aug 12, 2016
…r_set_config

Since commit 0955c1250e96 ("drm/crtc: take references to connectors used
in a modeset. (v2)"), the reference counts of all connectors in the
drm_mode_set given to drm_crtc_helper_set_config are incremented, and then
the reference counts of all connectors are decremented on success, but in a
temporary copy of the connector structure. This leads to the following
error after the first modeset on imx-drm:

    Unable to handle kernel NULL pointer dereference at virtual address 00000004
    pgd = ad8c4000
    [00000004] *pgd=3d9c5831, *pte=00000000, *ppte=00000000
    Internal error: Oops: 817 [#1] PREEMPT SMP ARM
    Modules linked in:
    CPU: 1 PID: 190 Comm: kmsfb-manage Not tainted 4.7.0-rc1+ #657
    Hardware name: Freescale i.MX6 Quad/DualLit: [<80506098>]    lr : [<80252e94>]    psr: 200c0013
    sp : adca7ca8  ip : adca7b90  fp : adca7cd4
    r10: 00000000  r9 : 00000100  r8 : 00000200
    r7 : af3c9800  r6 : aded7848  r5 : aded7800  r4 : 00000000
    r3 : af3ca058  r2 : 00000200  r1 : af3ca058  r0 : 00000000
    Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
    Control: 10c5387d  Table: 3d8c404a  DAC: 00000051
    Process kmsfb-manage (pid: 190, stack limit = 0xadca6210)
    Stack: (0xadca7ca8 to 0xadca8000)
    7ca0:                   805190e0 aded7800 aded7820 80501a88 8155a290 af3c9c6c
    7cc0: adca7ddc 0000000f adca7cec adca7cd8 80519104 80506044 805190e0 aded7800
    7ce0: adca7d04 adca7cf0 80501ac0 805190ec aded7820 aded7814 adca7d24 adca7d08
    7d00: 804fdb80 80501a94 aded7800 af3ca010 aded7afc af3c9c60 adca7d94 adca7d28
    7d20: 804e3518 804fdb20 00000000 af3c9b1c adca7d50 81506f44 00000000 8093c500
    7d40: af3c9c6c ae4f2ca8 ae4f2c18 00000000 00000000 ae637f00 00000000 aded7800
    7d60: 00000001 af3c9800 af23c300 ae77fcc0 ae4f2c18 00000001 af3c9800 8155a290
    7d80: af1af700 adca6000 adca7db4 adca7d98 804fea6c 804e2de4 adca7e50 adb3d940
    7da0: 00000001 af3c9800 adca7e24 adca7db8 8050440c 804fea0c ae77fcc0 00000003
    7dc0: adca7e24 adb3d940 af1af700 ae77fcc0 ae77fccc ae4f2c18 8083d44c ae77fcc0
    7de0: ae4002 80d03040 adca7e64 adca7e40 adca7e50 80503f08
    7e40: 7ebd5630 adca7e50 00000068 c06864a2 7ebd5be8 00000000 00000001 00000018
    7e60: 00000026 00000000 00000000 00000000 00000001 000115bc 05010500 05a0059f
    7e80: 03200000 03360321 00000337 0000003c 00000000 00000040 30383231 30303878
    7ea0: 00000000 00000000 00000000 00000000 00000000 00000000 80173058 80172e30
    7ec0: 80d77d32 00004000 adf7d900 00000003 00000000 7ebd5630 af342bb0 adfe3b80
    7ee0: 80272f50 00000003 adca6000 00000000 adca7f7c adca7f00 802725ec 804f52cc
    7f00: 802809cc 80178450 00000000 00000000 80280880 80145904 adb3d8c0 adf7d990
    7f20: ffffffff 00000003 00004000 01614c10 c06864a2 00000003 adca6000 00000000
    7f40: adca7f6c adca7f50 80280b04 8028088c 000115bc adfe3b81 7ebd5630 adfe3b80
    7f60: c06864a2 00000003 adca6000 00000000 adca7fa4 adca7f80 80272f50 80272548
    7f80: 000115bc 00017050 00000001 01614c10 00000036 801089e4 00000000 adca7fa8
    7fa0: 80108840 80272f18 00017050 00000001 00000003 c06864a2 7ebd5630 000115bc
    7fc0: 00017050 00000001 01614c10 00000036 00000003 00000000 00000026 00000018
    7fe0: 00016f38 7ebd562c 0000b5e9 76ef31e6 400c0030 00000003 ff5f37db bfe7dd4d
    Backtrace:
    [<80506038>] (drm_connector_cleanup) from [<80519104>] (dw_hdmi_connector_destroy+0x24/0x28)
     r10:0000000f r9:adca7ddc r8:af3c9c6c r7:8155a290 r6:80501a88 r5:aded7820
     r4:aded7800 r3:805190e0
    [<805190e0>] (dw_hdmi_connector_destroy) from [<80501ac0>] (drm_connector_free+0x38/0x3c)
     r4:aded7800 nreference) from [<804e3518>] (drm_crtc_helper_set_config+0x740/0xbf4)
     r6:af3c9c60 r5:aded7afc r4:af3ca010 r3:aded7800
    [<804e2dd8>] (drm_crtc_helper_set_config) from [<804fea6c>] (drm_mode_set_config_internal+0x6c/0xf4)
     r10:adca6000 r9:af1af700 r8:8155a290 r7:af3c9800 r6:00000001 r5:ae4f2c18
     r4:ae77fcc0
    [<804fea00>] (drm_mode_set_config_internal) from [<8050440c>] (drm_mode_setcrtc+0x504/0x57c)
     r7:af3c9800 r6:00000001 r5:adb3d940 r4:adca7e50
    [<80503f08>] (drm_mode_setcrtc) from [<804f5404>] (drm_ioctl+0x144/0x4dc)
     r10:ada2e000 r9:000000a2 r8:af3c9800 r7:8155a290 r6:809320b4 r5:00000051
     r4:adca7e50
    [<804f52c0>] (drm_ioctl) from [<802725ec>] (do_vfs_ioctl+0xb0/0x9d0)
     r10:00000000 r9:adca6000 r8:00000003 r7:80272f50 r6:adfe3b80 r5:af342bb0
     r4:7ebd5630
    [<8027253c>] (do_vfs_ioctl) from [<80272f50>] (SyS_ioctl+0x44/0x6c)
     r10:00000000 r9:adca6000 r8:00000003 r7:c06864a2 r6:adfe3b80 r5:7ebd5630
     r4:adfe3b81
    [<80272f0c>] (SyS_ioctl) from [<80108840>] (ret_fast_syscall+0x0/0x1c)
     r8:801089e4 r7:00000036 r6:01614c10 r5:00000001 r4:00017050 r3:000115bc
    Code: 0a00000c e5932004 e1a01003 e1a0a004 (e5842004)
    ---[ end trace 9a7257572ccacb16 ]---

Only the reference count of connectors that weren't previously bound to
an encoder should be incremented after a call to drm_crtc_helper_set_config.
And only the reference count of connectors that were previously bound to
an encoder and are unbound afterwards should ever be decremented.
The reference counts of the temporary copies in the save_connectors
should not be touched at all.

This patch fixes the above error by only incrementing the reference count
of those connectors in the set that are initially not bound to any encoder,
and also by restoring the reference count of only those connectors in the
set in the failure case.

"Note that this can only be hit when fbdev emulation is disabled, since
then the refcount drops from 1 to 0 and we call the connector destroy
functions on the backup copy, which eventually results in tears. With
fbdev emulation the refcount only goes down from 2 to 1 ever. And since we
unconditionally increment the refcount on the real object, the refcount of
that will slowly increase. The backup connector's refcount doesn't matter,
since we kfree() that either way in the end of
drm_crtc_helper_set_config()."

Fixes: 0955c1250e96 ("drm/crtc: take references to connectors used in a modeset. (v2)")
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
mattmacy pushed a commit that referenced this issue Aug 15, 2016
0-day kbuilder found

[    1.360244] BUG: unable to handle kernel NULL pointer dereference at   (null)
[    1.360972] IP: [<c14db9ad>] mutex_lock_nested+0x11f/0x2c3
[    1.361512] *pde = 00000000
[    1.361827] Oops: 0002 [#1]
[    1.362123] Modules linked in:
[    1.362451] CPU: 0 PID: 1 Comm: swapper Not tainted 4.7.0-rc2-00564-ge28cd4d #1
[    1.363202] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
[    1.364105] task: c03d0000 ti: d28da000 task.ti: d28da000
[    1.364636] EIP: 0060:[<c14db9ad>] EFLAGS: 00210096 CPU: 0
[    1.365215] EIP is at mutex_lock_nested+0x11f/0x2c3
[    1.365703] EAX: 00000000 EBX: d39e8ae8 ECX: d39e8b14 EDX: c1361cf9
[    1.366351] ESI: c03d0000 EDI: d28dbed0 EBP: d28dbeec ESP: d28dbec0
[    1.367010]  DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
[    1.367534] CR0: 80050033 CR2: 00000000 CR3: 019a9000 CR4: 00000690
[    1.368152] Stack:
[    1.368356]  d39e8b14 d39e8b24 c1361cf9 00200246 d39e8b14 00000000 11111111 d28dbed0
[    1.369235]  d39e8800 d39e8ae8 00000000 d28dbf08 c1361cf9 d28dbf0c c10b25be d39e8800
[    1.370087]  00000000 00000000 d28dbf1c c135e37d fffffff4 ffffffff 00000000 d28dbf28
[    1.371012] Call Trace:
[    1.371272]  [<c1361cf9>] ? drm_connector_register_all+0x1a/0x92
[    1.371847]  [<c1361cf9>] drm_connector_register_all+0x1a/0x92
[    1.372421]  [<c10b25be>] ? kstrdup+0x25/0x3a
[    1.372863]  [<c135e37d>] drm_dev_register+0x59/0x99
[    1.373358]  [<c195ea3e>] vgem_init+0x34/0x49
[    1.373770]  [<c195ea0a>] ? mipi_dsi_bus_init+0xf/0xf
[    1.374257]  [<c100048f>] do_one_initcall+0x7c/0xfd
[    1.374754]  [<c104b409>] ? parse_args+0x1fd/0x314
[    1.375259]  [<c1939c10>] ? kernel_init_freeable+0xd0/0x179
[    1.375837]  [<c1939c2c>] kernel_init_freeable+0xec/0x179
[    1.376371]  [<c14d66ea>] kernel_init+0x8/0xcb
[    1.376806]  [<c14debce>] ret_from_kernel_thread+0xe/0x30
[    1.377322]  [<c14d66e2>] ? rest_init+0x10e/0x10e
[    1.377754] Code: 89 fa e8 71 c5 b7 ff 8b 4e 04 89 fa 89 d8 e8 8e c6 b7 ff 8d 43 2c 89 45 d4 8b 43 30 8d 4b 2c 89 45 e8 89 7b 30 89 4d e4 8b 55 dc <89> 38 8d 43 3c 89 75 ec e8 c9 dd b7 ff eb 0c 31 c0 87 03 48
+75
[    1.380442] EIP: [<c14db9ad>] mutex_lock_nested+0x11f/0x2c3 SS:ESP 0068:d28dbec0
[    1.381174] CR2: 0000000000000000

when loading the non-modesetting vGEM module. To prevent use of the
uninitialised dev->mode_config from drm_dev_register() we move the
drm_connector_register_all() under a DRIVER_MODESET guard. Longer term,
we probably want to initialise the embedded dev->mode_config automatically
from drm_dev_init() for all DRIVER_MODESET drivers.

v2: Also protect drm_dev_unregister.

Fixes: e28cd4d0a223 ("drm: Automatically register/unregister all connectors")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Testcase: igt/vgem_reload_basic
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1466257601-5656-1-git-send-email-chris@chris-wilson.co.uk
mattmacy pushed a commit that referenced this issue Aug 16, 2016
drm_connector_register_all requires a few too many locks because our
connector_list locking is busted. Add another FIXME+hack to work
around this. This should address the below lockdep splat:

======================================================
[ INFO: possible circular locking dependency detected ]
4.7.0-rc5+ #524 Tainted: G           O
-------------------------------------------------------
kworker/u8:0/6 is trying to acquire lock:
 (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120

but task is already holding lock:
 ((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810ac195>] __blocking_notifier_call_chain+0x35/0x70

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 ((fb_notifier_list).rwsem){++++.+}:
       [<ffffffff810df611>] lock_acquire+0xb1/0x200
       [<ffffffff819a55b4>] down_write+0x44/0x80
       [<ffffffff810abf91>] blocking_notifier_chain_register+0x21/0xb0
       [<ffffffff814c7448>] fb_register_client+0x18/0x20
       [<ffffffff814c6c86>] backlight_device_register+0x136/0x260
       [<ffffffffa0127eb2>] intel_backlight_device_register+0xa2/0x160 [i915]
       [<ffffffffa00f46be>] intel_connector_register+0xe/0x10 [i915]
       [<ffffffffa0112bfb>] intel_dp_connector_register+0x1b/0x80 [i915]
       [<ffffffff8159dfea>] drm_connector_register+0x4a/0x80
       [<ffffffff8159fe44>] drm_connector_register_all+0x64/0xf0
       [<ffffffff815a2a64>] drm_modeset_register_all+0x174/0x1c0
       [<ffffffff81599b72>] drm_dev_register+0xc2/0xd0
       [<ffffffffa00621d7>] i915_driver_load+0x1547/0x2200 [i915]
       [<ffffffffa006d80f>] i915_pci_probe+0x4f/0x70 [i915]
       [<ffffffff814a2135>] local_pci_probe+0x45/0xa0
       [<ffffffff814a349b>] pci_device_probe+0xdb/0x130
       [<ffffffff815c07e3>] driver_probe_device+0x223/0x440
       [<ffffffff815c0ad5>] __driver_attach+0xd5/0x100
       [<ffffffff815be386>] bus_for_each_dev+0x66/0xa0
       [<ffffffff815c002e>] driver_attach+0x1e/0x20
       [<ffffffff815bf9be>] bus_add_driver+0x1ee/0x280
       [<ffffffff815c1810>] driver_register+0x60/0xe0
       [<ffffffff814a1a10>] __pci_register_driver+0x60/0x70
       [<ffffffffa01a905b>] i915_init+0x5b/0x62 [i915]
       [<ffffffff8100042d>] do_one_initcall+0x3d/0x150
       [<ffffffff811a935b>] do_init_module+0x5f/0x1d9
       [<ffffffff81124416>] load_module+0x20e6/0x27e0
       [<ffffffff81124d63>] SYSC_finit_module+0xc3/0xf0
       [<ffffffff81124dae>] SyS_finit_module+0xe/0x10
       [<ffffffff819a83a9>] entry_SYSCALL_64_fastpath+0x1c/0xac

-> #0 (&dev->mode_config.mutex){+.+.+.}:
       [<ffffffff810df0ac>] __lock_acquire+0x10fc/0x1260
       [<ffffffff810df611>] lock_acquire+0xb1/0x200
       [<ffffffff819a3097>] mutex_lock_nested+0x67/0x3c0
       [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120
       [<ffffffff8158f79b>] drm_fb_helper_restore_fbdev_mode_unlocked+0x2b/0x80
       [<ffffffff8158f81d>] drm_fb_helper_set_par+0x2d/0x50
       [<ffffffffa0105f7a>] intel_fbdev_set_par+0x1a/0x60 [i915]
       [<ffffffff814c13c6>] fbcon_init+0x586/0x610
       [<ffffffff8154d16a>] visual_init+0xca/0x130
       [<ffffffff8154e611>] do_bind_con_driver+0x1c1/0x3a0
       [<ffffffff8154eaf6>] do_take_over_console+0x116/0x180
       [<ffffffff814bd3a7>] do_fbcon_takeover+0x57/0xb0
       [<ffffffff814c1e48>] fbcon_event_notify+0x658/0x750
       [<ffffffff810abcae>] notifier_call_chain+0x3e/0xb0
       [<ffffffff810ac1ad>] __blocking_notifier_call_chain+0x4d/0x70
       [<ffffffff810ac1e6>] blocking_notifier_call_chain+0x16/0x20
       [<ffffffff814c748b>] fb_notifier_call_chain+0x1b/0x20
       [<ffffffff814c86b1>] register_framebuffer+0x251/0x330
       [<ffffffff8158fa9f>] drm_fb_helper_initial_config+0x25f/0x3f0
       [<ffffffffa0106b48>] intel_fbdev_initial_config+0x18/0x30 [i915]
       [<ffffffff810adfd8>] async_run_entry_fn+0x48/0x150
       [<ffffffff810a3947>] process_one_work+0x1e7/0x750
       [<ffffffff810a3efb>] worker_thread+0x4b/0x4f0
       [<ffffffff810aad4f>] kthread+0xef/0x110
       [<ffffffff819a85ef>] ret_from_fork+0x1f/0x40

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock((fb_notifier_list).rwsem);
                               lock(&dev->mode_config.mutex);
                               lock((fb_notifier_list).rwsem);
  lock(&dev->mode_config.mutex);

 *** DEADLOCK ***

6 locks held by kworker/u8:0/6:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff810a38c9>] process_one_work+0x169/0x750
 #1:  ((&entry->work)){+.+.+.}, at: [<ffffffff810a38c9>] process_one_work+0x169/0x750
 #2:  (registration_lock){+.+.+.}, at: [<ffffffff814c8487>] register_framebuffer+0x27/0x330
 #3:  (console_lock){+.+.+.}, at: [<ffffffff814c86ce>] register_framebuffer+0x26e/0x330
 #4:  (&fb_info->lock){+.+.+.}, at: [<ffffffff814c78dd>] lock_fb_info+0x1d/0x40
 #5:  ((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810ac195>] __blocking_notifier_call_chain+0x35/0x70

stack backtrace:
CPU: 2 PID: 6 Comm: kworker/u8:0 Tainted: G           O    4.7.0-rc5+ #524
Hardware name: Intel Corp. Broxton P/NOTEBOOK, BIOS APLKRVPA.X64.0138.B33.1606250842 06/25/2016
Workqueue: events_unbound async_run_entry_fn
 0000000000000000 ffff8800758577f0 ffffffff814507a5 ffffffff828b9900
 ffffffff828b9900 ffff880075857830 ffffffff810dc6fa ffff880075857880
 ffff88007584d688 0000000000000005 0000000000000006 ffff88007584d6b0
Call Trace:
 [<ffffffff814507a5>] dump_stack+0x67/0x92
 [<ffffffff810dc6fa>] print_circular_bug+0x1aa/0x200
 [<ffffffff810df0ac>] __lock_acquire+0x10fc/0x1260
 [<ffffffff810df611>] lock_acquire+0xb1/0x200
 [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
 [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
 [<ffffffff819a3097>] mutex_lock_nested+0x67/0x3c0
 [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
 [<ffffffff810fa85f>] ? rcu_read_lock_sched_held+0x7f/0x90
 [<ffffffff81208218>] ? kmem_cache_alloc_trace+0x248/0x2b0
 [<ffffffff815afdc5>] ? drm_modeset_lock_all+0x25/0x120
 [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120
 [<ffffffff8158f79b>] drm_fb_helper_restore_fbdev_mode_unlocked+0x2b/0x80
 [<ffffffff8158f81d>] drm_fb_helper_set_par+0x2d/0x50
 [<ffffffffa0105f7a>] intel_fbdev_set_par+0x1a/0x60 [i915]
 [<ffffffff814c13c6>] fbcon_init+0x586/0x610
 [<ffffffff8154d16a>] visual_init+0xca/0x130
 [<ffffffff8154e611>] do_bind_con_driver+0x1c1/0x3a0
 [<ffffffff8154eaf6>] do_take_over_console+0x116/0x180
 [<ffffffff814bd3a7>] do_fbcon_takeover+0x57/0xb0
 [<ffffffff814c1e48>] fbcon_event_notify+0x658/0x750
 [<ffffffff810abcae>] notifier_call_chain+0x3e/0xb0
 [<ffffffff810ac1ad>] __blocking_notifier_call_chain+0x4d/0x70
 [<ffffffff810ac1e6>] blocking_notifier_call_chain+0x16/0x20
 [<ffffffff814c748b>] fb_notifier_call_chain+0x1b/0x20
 [<ffffffff814c86b1>] register_framebuffer+0x251/0x330
 [<ffffffff815b7e8d>] ? vga_switcheroo_client_fb_set+0x5d/0x70
 [<ffffffff8158fa9f>] drm_fb_helper_initial_config+0x25f/0x3f0
 [<ffffffffa0106b48>] intel_fbdev_initial_config+0x18/0x30 [i915]
 [<ffffffff810adfd8>] async_run_entry_fn+0x48/0x150
 [<ffffffff810a3947>] process_one_work+0x1e7/0x750
 [<ffffffff810a38c9>] ? process_one_work+0x169/0x750
 [<ffffffff810a3efb>] worker_thread+0x4b/0x4f0
 [<ffffffff810a3eb0>] ? process_one_work+0x750/0x750
 [<ffffffff810aad4f>] kthread+0xef/0x110
 [<ffffffff819a85ef>] ret_from_fork+0x1f/0x40
 [<ffffffff810aac60>] ? kthread_stop+0x2e0/0x2e0

v2: Rebase onto the right branch (hand-editing patches ftw) and add more
reporters.

Reported-by: Imre Deak <imre.deak@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Reported-by: Jiri Kosina <jikos@kernel.org>
Cc: Jiri Kosina <jikos@kernel.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
@dwrobison dwrobison mentioned this issue Oct 4, 2016
mattmacy pushed a commit that referenced this issue Dec 26, 2016
If we hit the error path, we have never called drm_encoder_init() and so
have nothing to cleanup. Doing so hits a null dereference:

[   10.066261] BUG: unable to handle kernel NULL pointer dereference at 00000104
[   10.066273] IP: [<c16054b4>] mutex_lock+0xa/0x15
[   10.066287] *pde = 00000000
[   10.066295] Oops: 0002 [#1]
[   10.066302] Modules linked in: i915(+) video i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm iTCO_wdt iTCO_vendor_support ppdev evdev snd_intel8x0 snd_ac97_codec ac97_bus psmouse snd_pcm snd_timer snd pcspkr uhci_hcd ehci_pci soundcore sr_mod ehci_hcd serio_raw i2c_i801 usbcore i2c_smbus cdrom lpc_ich mfd_core rng_core e100 mii floppy parport_pc parport acpi_cpufreq button processor usb_common eeprom lm85 hwmon_vid autofs4
[   10.066378] CPU: 0 PID: 132 Comm: systemd-udevd Not tainted 4.8.0-rc3-00013-gef0e1ea #34
[   10.066389] Hardware name: MicroLink                               /D865GLC                        , BIOS BF86510A.86A.0077.P25.0508040031 08/04/2005
[   10.066401] task: f62db800 task.stack: f5970000
[   10.066409] EIP: 0060:[<c16054b4>] EFLAGS: 00010286 CPU: 0
[   10.066417] EIP is at mutex_lock+0xa/0x15
[   10.066424] EAX: 00000104 EBX: 00000104 ECX: 00000000 EDX: 80000000
[   10.066432] ESI: 00000000 EDI: 00000104 EBP: f5be8000 ESP: f5971b58
[   10.066439]  DS: 007b ES: 007b FS: 0000 GS: 00e0 SS: 0068
[   10.066446] CR0: 80050033 CR2: 00000104 CR3: 35945000 CR4: 000006d0
[   10.066453] Stack:
[   10.066459]  f503d740 f824dddf 00000000 f61170c0 f61170c0 f82371ae f850f40e 00000001
[   10.066476]  f61170c0 f5971bcc f5be8000 f9c2d401 00000001 f8236fcc 00000001 00000000
[   10.066491]  f5144014 f5be8104 00000008 f9c5267c 00000007 f61170c0 f5144400 f9c4ff00
[   10.066507] Call Trace:
[   10.066526]  [<f824dddf>] ? drm_modeset_lock_all+0x27/0xb3 [drm]
[   10.066545]  [<f82371ae>] ? drm_encoder_cleanup+0x1a/0x132 [drm]
[   10.066559]  [<f850f40e>] ? drm_atomic_helper_connector_reset+0x3f/0x5c [drm_kms_helper]
[   10.066644]  [<f9c2d401>] ? intel_dvo_init+0x569/0x788 [i915]
[   10.066663]  [<f8236fcc>] ? drm_encoder_init+0x43/0x20b [drm]
[   10.066734]  [<f9bf1fce>] ? intel_modeset_init+0x1436/0x17dd [i915]
[   10.066791]  [<f9b37636>] ? i915_driver_load+0x85a/0x15d3 [i915]
[   10.066846]  [<f9b3603d>] ? i915_driver_open+0x5/0x5 [i915]
[   10.066857]  [<c14af4d0>] ? firmware_map_add_entry.part.2+0xc/0xc
[   10.066868]  [<c1343daf>] ? pci_device_probe+0x8e/0x11c
[   10.066878]  [<c140cec8>] ? driver_probe_device+0x1db/0x62e
[   10.066888]  [<c120c010>] ? kernfs_new_node+0x29/0x9c
[   10.066897]  [<c13438e0>] ? pci_match_device+0xd9/0x161
[   10.066905]  [<c120c48b>] ? kernfs_create_dir_ns+0x42/0x88
[   10.066914]  [<c140d401>] ? __driver_attach+0xe6/0x11b
[   10.066924]  [<c1303b13>] ? kobject_add_internal+0x1bb/0x44f
[   10.066933]  [<c140d31b>] ? driver_probe_device+0x62e/0x62e
[   10.066941]  [<c140a2d2>] ? bus_for_each_dev+0x46/0x7f
[   10.066950]  [<c140c502>] ? driver_attach+0x1a/0x34
[   10.066958]  [<c140d31b>] ? driver_probe_device+0x62e/0x62e
[   10.066966]  [<c140b758>] ? bus_add_driver+0x217/0x32a
[   10.066975]  [<f8403000>] ? 0xf8403000
[   10.066982]  [<c140de27>] ? driver_register+0x5f/0x108
[   10.066991]  [<c1000493>] ? do_one_initcall+0x49/0x1f6
[   10.067000]  [<c1082299>] ? pick_next_task_fair+0x14b/0x2a3
[   10.067008]  [<c1603c8d>] ? __schedule+0x15c/0x4fe
[   10.067016]  [<c1604104>] ? preempt_schedule_common+0x19/0x3c
[   10.067027]  [<c11051de>] ? do_init_module+0x17/0x230
[   10.067035]  [<c1604139>] ? _cond_resched+0x12/0x1a
[   10.067044]  [<c116f9aa>] ? kmem_cache_alloc+0x8f/0x11f
[   10.067052]  [<c11051de>] ? do_init_module+0x17/0x230
[   10.067060]  [<c11703dd>] ? kfree+0x137/0x203
[   10.067068]  [<c110523d>] ? do_init_module+0x76/0x230
[   10.067078]  [<c10cadf3>] ? load_module+0x2a39/0x333f
[   10.067087]  [<c10cb8b2>] ? SyS_finit_module+0x96/0xd5
[   10.067096]  [<c1132231>] ? vm_mmap_pgoff+0x79/0xa0
[   10.067105]  [<c1001e96>] ? do_fast_syscall_32+0xb5/0x1b0
[   10.067114]  [<c16086a6>] ? sysenter_past_esp+0x47/0x75
[   10.067121] Code: c8 f7 76 c1 e8 8e cc d2 ff e9 45 fe ff ff 66 90 66 90 66 90 66 90 90 ff 00 7f 05 e8 4e 0c 00 00 c3 53 89 c3 e8 75 ec ff ff 89 d8 <ff> 08 79 05 e8 fa 0a 00 00 5b c3 53 89 c3 85 c0 74 1b 8b 03 83
[   10.067180] EIP: [<c16054b4>] mutex_lock+0xa/0x15 SS:ESP 0068:f5971b58
[   10.067190] CR2: 0000000000000104
[   10.067222] ---[ end trace 049f1f09da45a856 ]---

Reported-by: Meelis Roos <mroos@linux.ee>
Fixes: 580d8ed522e0 ("drm/i915: Give encoders useful names")
Reviewed-by: David Weinehall <david.weinehall@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160823092558.14931-1-chris@chris-wilson.co.uk
(cherry picked from commit 8f76aa0ebe0b7787afe768d9df80031e832d2520)
mattmacy pushed a commit that referenced this issue Dec 26, 2016
According to the CI test machines, SNB also uses the
GEN7_PCODE_MIN_FREQ_TABLE_GT_RATIO_OUT_OF_RANGE value to report a bad
GEN6_PCODE_MIN_FREQ_TABLE request.

[  157.744641] WARNING: CPU: 5 PID: 9238 at
drivers/gpu/drm/i915/intel_pm.c:7760 sandybridge_pcode_write+0x141/0x200 [i915]
[  157.744642] Missing switch case (16) in gen6_check_mailbox_status
[  157.744642] Modules linked in: snd_hda_intel i915 ax88179_178a usbnet mii x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core mei_me lpc_ich snd_pcm mei broadcom bcm_phy_lib tg3 ptp pps_core [last unloaded: vgem]
[  157.744658] CPU: 5 PID: 9238 Comm: drv_hangman Tainted: G     U  W 4.8.0-rc3-CI-CI_DRM_1589+ #1
[  157.744658] Hardware name: Dell Inc. XPS 8300  /0Y2MRG, BIOS A06 10/17/2011
[  157.744659]  0000000000000000 ffff88011f093a98 ffffffff81426415 ffff88011f093ae8
[  157.744662]  0000000000000000 ffff88011f093ad8 ffffffff8107d2a6 00001e50810d3c9f
[  157.744663]  ffff880128680000 0000000000000008 0000000000000000 ffff88012868a650
[  157.744665] Call Trace:
[  157.744669]  [<ffffffff81426415>] dump_stack+0x67/0x92
[  157.744672]  [<ffffffff8107d2a6>] __warn+0xc6/0xe0
[  157.744673]  [<ffffffff8107d30a>] warn_slowpath_fmt+0x4a/0x50
[  157.744685]  [<ffffffffa0029831>] sandybridge_pcode_write+0x141/0x200 [i915]
[  157.744697]  [<ffffffffa002a88a>] intel_enable_gt_powersave+0x64a/0x1330 [i915]
[  157.744712]  [<ffffffffa006b4cb>] ? i9xx_emit_request+0x1b/0x80 [i915]
[  157.744725]  [<ffffffffa0055ed3>] __i915_add_request+0x1e3/0x370 [i915]
[  157.744738]  [<ffffffffa00428bd>] i915_gem_do_execbuffer.isra.16+0xced/0x1b80 [i915]
[  157.744740]  [<ffffffff811a232e>] ? __might_fault+0x3e/0x90
[  157.744752]  [<ffffffffa0043b72>] i915_gem_execbuffer2+0xc2/0x2a0 [i915]
[  157.744753]  [<ffffffff815485b7>] drm_ioctl+0x207/0x4c0
[  157.744765]  [<ffffffffa0043ab0>] ? i915_gem_execbuffer+0x360/0x360 [i915]
[  157.744767]  [<ffffffff810ea4ad>] ?  debug_lockdep_rcu_enabled+0x1d/0x20
[  157.744769]  [<ffffffff811fe09e>] do_vfs_ioctl+0x8e/0x680
[  157.744770]  [<ffffffff811a2377>] ? __might_fault+0x87/0x90
[  157.744771]  [<ffffffff811a232e>] ? __might_fault+0x3e/0x90
[  157.744773]  [<ffffffff810d3df2>] ?  trace_hardirqs_on_caller+0x122/0x1b0
[  157.744774]  [<ffffffff811fe6cc>] SyS_ioctl+0x3c/0x70
[  157.744776]  [<ffffffff8180fe69>] entry_SYSCALL_64_fastpath+0x1c/0xac

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97491
Fixes: 87660502f1a4 ("drm/i915/gen6+: Interpret mailbox error flags")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Lyude <cpaul@redhat.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://patchwork.freedesktop.org/patch/msgid/20160826105926.3413-1-chris@chris-wilson.co.uk
Acked-by: Mika Kuoppala <mika.kuoppala@intel.com>
(cherry picked from commit 7850d1c35344c7bd6a357240f2f9f60fc2c097b5)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
mattmacy pushed a commit that referenced this issue Dec 28, 2016
What I never hit in testing, but Mika immediately did, was a GPU hang
with a pending fence release (where a tiled object has been changed by
the user to be untiled, and the update has not yet been committed to the
fence register). As the stride/tiling is 0, this causes a divide-by-zero
error when trying to write the new fence parameters:

[   28.784518] drm/i915: Resetting chip after gpu hang
[   28.784551] divide error: 0000 [#1] PREEMPT SMP
[   28.784565] Modules linked in: nls_iso8859_1 nls_cp437 vfat fat mxm_wmi x86_pkg_temp_thermal snd_hda_codec_hdmi kvm irqbypass snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec serio_raw snd_hwdep snd_hda_core snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_timer snd_seq_device snd soundcore mac_hid wmi efivarfs autofs4 raid10 raid456 libcrc32c async_raid6_recov async_memcpy async_pq raid6_pq async_xor xor async_tx raid0 multipath linear psmouse e1000e ptp pps_core nvme nvme_core i915 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm video
[   28.784738] CPU: 0 PID: 1692 Comm: kworker/0:2 Not tainted 4.8.0-rc2+ #895
[   28.784752] Hardware name: System manufacturer System Product Name/Z170M-PLUS, BIOS 1803 05/09/2016
[   28.784786] Workqueue: events_long i915_hangcheck_elapsed [i915]
[   28.784814] task: ffff923c18f59d40 task.stack: ffff923c1b7e4000
[   28.784827] RIP: 0010:[<ffffffffc0475b5f>]  [<ffffffffc0475b5f>] fence_write+0x9f/0x3b0 [i915]
[   28.784854] RSP: 0018:ffff923c1b7e7b30  EFLAGS: 00010246
[   28.784866] RAX: 00000000008ca000 RBX: ffff923c18540000 RCX: 0000000000000020
[   28.784880] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000596d000
[   28.784894] RBP: ffff923c1b7e7b68 R08: 0000000000000000 R09: 0000000000000000
[   28.784908] R10: 0000000000000000 R11: 00000000008ca000 R12: ffff923c1ef9d600
[   28.784921] R13: 0000000000100040 R14: 0000000000100044 R15: ffff923c18549908
[   28.784935] FS:  0000000000000000(0000) GS:ffff923c36c00000(0000) knlGS:0000000000000000
[   28.784951] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   28.784962] CR2: 00007f193373c893 CR3: 0000000419c78000 CR4: 00000000003406f0
[   28.784976] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   28.784990] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   28.785004] Stack:
[   28.785009]  000000000596c03b ffff923c1b7e7b68 ffff923c18549938 0000000000000009
[   28.785026]  ffff923c18540000 ffff923c18549280 ffff923c18547ce8 ffff923c1b7e7b90
[   28.785044]  ffffffffc04761f9 ffff923c18540000 ffff923c18547d00 ffff923c18548ff8
[   28.785062] Call Trace:
[   28.785078]  [<ffffffffc04761f9>] i915_gem_restore_fences+0x39/0x50 [i915]
[   28.785102]  [<ffffffffc047fe89>] i915_gem_reset+0x179/0x300 [i915]

Reported-by: Mika Kuoppala <mika.kuoppala@intel.com>
Fixes: 49ef5294cda2 ("drm/i915: Move fence tracking from object to vma")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160819155428.1670-1-chris@chris-wilson.co.uk
mattmacy pushed a commit that referenced this issue Dec 28, 2016
…_info

An unlikely ABBA deadlock in debugfs that no one has reported.

[  284.922349] ======================================================
[  284.922355] [ INFO: possible circular locking dependency detected ]
[  284.922361] 4.8.0-rc2+ #430 Tainted: G        W
[  284.922366] -------------------------------------------------------
[  284.922371] cat/1197 is trying to acquire lock:
[  284.922376]  (&dev->filelist_mutex){+.+...}, at: [<ffffffffa0055ba2>] i915_ppgtt_info+0x82/0x390 [i915]
[  284.922423]
[  284.922423] but task is already holding lock:
[  284.922429]  (&dev->struct_mutex){+.+.+.}, at: [<ffffffffa0055b55>] i915_ppgtt_info+0x35/0x390 [i915]
[  284.922465]
[  284.922465] which lock already depends on the new lock.
[  284.922465]
[  284.922471]
[  284.922471] the existing dependency chain (in reverse order) is:
[  284.922477]
-> #1 (&dev->struct_mutex){+.+.+.}:
[  284.922493]        [<ffffffff81087710>] lock_acquire+0x60/0x80
[  284.922505]        [<ffffffff8143e96f>] mutex_lock_nested+0x5f/0x360
[  284.922520]        [<ffffffffa004f877>] print_context_stats+0x37/0xf0 [i915]
[  284.922549]        [<ffffffffa00535f5>] i915_gem_object_info+0x265/0x490 [i915]
[  284.922581]        [<ffffffff81144491>] seq_read+0xe1/0x3b0
[  284.922592]        [<ffffffff811f77b3>] full_proxy_read+0x83/0xb0
[  284.922604]        [<ffffffff8111ba03>] __vfs_read+0x23/0x110
[  284.922616]        [<ffffffff8111c9b9>] vfs_read+0x89/0x110
[  284.922626]        [<ffffffff8111dbf4>] SyS_read+0x44/0xa0
[  284.922636]        [<ffffffff81442be9>] entry_SYSCALL_64_fastpath+0x1c/0xac
[  284.922648]
-> #0 (&dev->filelist_mutex){+.+...}:
[  284.922667]        [<ffffffff810871fc>] __lock_acquire+0x10fc/0x1270
[  284.922678]        [<ffffffff81087710>] lock_acquire+0x60/0x80
[  284.922689]        [<ffffffff8143e96f>] mutex_lock_nested+0x5f/0x360
[  284.922701]        [<ffffffffa0055ba2>] i915_ppgtt_info+0x82/0x390 [i915]
[  284.922729]        [<ffffffff81144491>] seq_read+0xe1/0x3b0
[  284.922739]        [<ffffffff811f77b3>] full_proxy_read+0x83/0xb0
[  284.922750]        [<ffffffff8111ba03>] __vfs_read+0x23/0x110
[  284.922761]        [<ffffffff8111c9b9>] vfs_read+0x89/0x110
[  284.922771]        [<ffffffff8111dbf4>] SyS_read+0x44/0xa0
[  284.922781]        [<ffffffff81442be9>] entry_SYSCALL_64_fastpath+0x1c/0xac
[  284.922793]
[  284.922793] other info that might help us debug this:
[  284.922793]
[  284.922809]  Possible unsafe locking scenario:
[  284.922809]
[  284.922818]        CPU0                    CPU1
[  284.922825]        ----                    ----
[  284.922831]   lock(&dev->struct_mutex);
[  284.922842]                                lock(&dev->filelist_mutex);
[  284.922854]                                lock(&dev->struct_mutex);
[  284.922865]   lock(&dev->filelist_mutex);
[  284.922875]
[  284.922875]  *** DEADLOCK ***
[  284.922875]
[  284.922888] 3 locks held by cat/1197:
[  284.922895]  #0:  (debugfs_srcu){......}, at: [<ffffffff811f7730>] full_proxy_read+0x0/0xb0
[  284.922919]  #1:  (&p->lock){+.+.+.}, at: [<ffffffff811443e8>] seq_read+0x38/0x3b0
[  284.922942]  #2:  (&dev->struct_mutex){+.+.+.}, at: [<ffffffffa0055b55>] i915_ppgtt_info+0x35/0x390 [i915]
[  284.922983]

Fixes: 1d2ac403ae3b ("drm: Protect dev->filelist with its own mutex")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160822132820.21725-1-chris@chris-wilson.co.uk
mattmacy pushed a commit that referenced this issue Dec 28, 2016
If we hit the error path, we have never called drm_encoder_init() and so
have nothing to cleanup. Doing so hits a null dereference:

[   10.066261] BUG: unable to handle kernel NULL pointer dereference at 00000104
[   10.066273] IP: [<c16054b4>] mutex_lock+0xa/0x15
[   10.066287] *pde = 00000000
[   10.066295] Oops: 0002 [#1]
[   10.066302] Modules linked in: i915(+) video i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm iTCO_wdt iTCO_vendor_support ppdev evdev snd_intel8x0 snd_ac97_codec ac97_bus psmouse snd_pcm snd_timer snd pcspkr uhci_hcd ehci_pci soundcore sr_mod ehci_hcd serio_raw i2c_i801 usbcore i2c_smbus cdrom lpc_ich mfd_core rng_core e100 mii floppy parport_pc parport acpi_cpufreq button processor usb_common eeprom lm85 hwmon_vid autofs4
[   10.066378] CPU: 0 PID: 132 Comm: systemd-udevd Not tainted 4.8.0-rc3-00013-gef0e1ea #34
[   10.066389] Hardware name: MicroLink                               /D865GLC                        , BIOS BF86510A.86A.0077.P25.0508040031 08/04/2005
[   10.066401] task: f62db800 task.stack: f5970000
[   10.066409] EIP: 0060:[<c16054b4>] EFLAGS: 00010286 CPU: 0
[   10.066417] EIP is at mutex_lock+0xa/0x15
[   10.066424] EAX: 00000104 EBX: 00000104 ECX: 00000000 EDX: 80000000
[   10.066432] ESI: 00000000 EDI: 00000104 EBP: f5be8000 ESP: f5971b58
[   10.066439]  DS: 007b ES: 007b FS: 0000 GS: 00e0 SS: 0068
[   10.066446] CR0: 80050033 CR2: 00000104 CR3: 35945000 CR4: 000006d0
[   10.066453] Stack:
[   10.066459]  f503d740 f824dddf 00000000 f61170c0 f61170c0 f82371ae f850f40e 00000001
[   10.066476]  f61170c0 f5971bcc f5be8000 f9c2d401 00000001 f8236fcc 00000001 00000000
[   10.066491]  f5144014 f5be8104 00000008 f9c5267c 00000007 f61170c0 f5144400 f9c4ff00
[   10.066507] Call Trace:
[   10.066526]  [<f824dddf>] ? drm_modeset_lock_all+0x27/0xb3 [drm]
[   10.066545]  [<f82371ae>] ? drm_encoder_cleanup+0x1a/0x132 [drm]
[   10.066559]  [<f850f40e>] ? drm_atomic_helper_connector_reset+0x3f/0x5c [drm_kms_helper]
[   10.066644]  [<f9c2d401>] ? intel_dvo_init+0x569/0x788 [i915]
[   10.066663]  [<f8236fcc>] ? drm_encoder_init+0x43/0x20b [drm]
[   10.066734]  [<f9bf1fce>] ? intel_modeset_init+0x1436/0x17dd [i915]
[   10.066791]  [<f9b37636>] ? i915_driver_load+0x85a/0x15d3 [i915]
[   10.066846]  [<f9b3603d>] ? i915_driver_open+0x5/0x5 [i915]
[   10.066857]  [<c14af4d0>] ? firmware_map_add_entry.part.2+0xc/0xc
[   10.066868]  [<c1343daf>] ? pci_device_probe+0x8e/0x11c
[   10.066878]  [<c140cec8>] ? driver_probe_device+0x1db/0x62e
[   10.066888]  [<c120c010>] ? kernfs_new_node+0x29/0x9c
[   10.066897]  [<c13438e0>] ? pci_match_device+0xd9/0x161
[   10.066905]  [<c120c48b>] ? kernfs_create_dir_ns+0x42/0x88
[   10.066914]  [<c140d401>] ? __driver_attach+0xe6/0x11b
[   10.066924]  [<c1303b13>] ? kobject_add_internal+0x1bb/0x44f
[   10.066933]  [<c140d31b>] ? driver_probe_device+0x62e/0x62e
[   10.066941]  [<c140a2d2>] ? bus_for_each_dev+0x46/0x7f
[   10.066950]  [<c140c502>] ? driver_attach+0x1a/0x34
[   10.066958]  [<c140d31b>] ? driver_probe_device+0x62e/0x62e
[   10.066966]  [<c140b758>] ? bus_add_driver+0x217/0x32a
[   10.066975]  [<f8403000>] ? 0xf8403000
[   10.066982]  [<c140de27>] ? driver_register+0x5f/0x108
[   10.066991]  [<c1000493>] ? do_one_initcall+0x49/0x1f6
[   10.067000]  [<c1082299>] ? pick_next_task_fair+0x14b/0x2a3
[   10.067008]  [<c1603c8d>] ? __schedule+0x15c/0x4fe
[   10.067016]  [<c1604104>] ? preempt_schedule_common+0x19/0x3c
[   10.067027]  [<c11051de>] ? do_init_module+0x17/0x230
[   10.067035]  [<c1604139>] ? _cond_resched+0x12/0x1a
[   10.067044]  [<c116f9aa>] ? kmem_cache_alloc+0x8f/0x11f
[   10.067052]  [<c11051de>] ? do_init_module+0x17/0x230
[   10.067060]  [<c11703dd>] ? kfree+0x137/0x203
[   10.067068]  [<c110523d>] ? do_init_module+0x76/0x230
[   10.067078]  [<c10cadf3>] ? load_module+0x2a39/0x333f
[   10.067087]  [<c10cb8b2>] ? SyS_finit_module+0x96/0xd5
[   10.067096]  [<c1132231>] ? vm_mmap_pgoff+0x79/0xa0
[   10.067105]  [<c1001e96>] ? do_fast_syscall_32+0xb5/0x1b0
[   10.067114]  [<c16086a6>] ? sysenter_past_esp+0x47/0x75
[   10.067121] Code: c8 f7 76 c1 e8 8e cc d2 ff e9 45 fe ff ff 66 90 66 90 66 90 66 90 90 ff 00 7f 05 e8 4e 0c 00 00 c3 53 89 c3 e8 75 ec ff ff 89 d8 <ff> 08 79 05 e8 fa 0a 00 00 5b c3 53 89 c3 85 c0 74 1b 8b 03 83
[   10.067180] EIP: [<c16054b4>] mutex_lock+0xa/0x15 SS:ESP 0068:f5971b58
[   10.067190] CR2: 0000000000000104
[   10.067222] ---[ end trace 049f1f09da45a856 ]---

Reported-by: Meelis Roos <mroos@linux.ee>
Fixes: 580d8ed522e0 ("drm/i915: Give encoders useful names")
Reviewed-by: David Weinehall <david.weinehall@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160823092558.14931-1-chris@chris-wilson.co.uk
mattmacy pushed a commit that referenced this issue Dec 28, 2016
According to the CI test machines, SNB also uses the
GEN7_PCODE_MIN_FREQ_TABLE_GT_RATIO_OUT_OF_RANGE value to report a bad
GEN6_PCODE_MIN_FREQ_TABLE request.

[  157.744641] WARNING: CPU: 5 PID: 9238 at
drivers/gpu/drm/i915/intel_pm.c:7760 sandybridge_pcode_write+0x141/0x200 [i915]
[  157.744642] Missing switch case (16) in gen6_check_mailbox_status
[  157.744642] Modules linked in: snd_hda_intel i915 ax88179_178a usbnet mii x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core mei_me lpc_ich snd_pcm mei broadcom bcm_phy_lib tg3 ptp pps_core [last unloaded: vgem]
[  157.744658] CPU: 5 PID: 9238 Comm: drv_hangman Tainted: G     U  W 4.8.0-rc3-CI-CI_DRM_1589+ #1
[  157.744658] Hardware name: Dell Inc. XPS 8300  /0Y2MRG, BIOS A06 10/17/2011
[  157.744659]  0000000000000000 ffff88011f093a98 ffffffff81426415 ffff88011f093ae8
[  157.744662]  0000000000000000 ffff88011f093ad8 ffffffff8107d2a6 00001e50810d3c9f
[  157.744663]  ffff880128680000 0000000000000008 0000000000000000 ffff88012868a650
[  157.744665] Call Trace:
[  157.744669]  [<ffffffff81426415>] dump_stack+0x67/0x92
[  157.744672]  [<ffffffff8107d2a6>] __warn+0xc6/0xe0
[  157.744673]  [<ffffffff8107d30a>] warn_slowpath_fmt+0x4a/0x50
[  157.744685]  [<ffffffffa0029831>] sandybridge_pcode_write+0x141/0x200 [i915]
[  157.744697]  [<ffffffffa002a88a>] intel_enable_gt_powersave+0x64a/0x1330 [i915]
[  157.744712]  [<ffffffffa006b4cb>] ? i9xx_emit_request+0x1b/0x80 [i915]
[  157.744725]  [<ffffffffa0055ed3>] __i915_add_request+0x1e3/0x370 [i915]
[  157.744738]  [<ffffffffa00428bd>] i915_gem_do_execbuffer.isra.16+0xced/0x1b80 [i915]
[  157.744740]  [<ffffffff811a232e>] ? __might_fault+0x3e/0x90
[  157.744752]  [<ffffffffa0043b72>] i915_gem_execbuffer2+0xc2/0x2a0 [i915]
[  157.744753]  [<ffffffff815485b7>] drm_ioctl+0x207/0x4c0
[  157.744765]  [<ffffffffa0043ab0>] ? i915_gem_execbuffer+0x360/0x360 [i915]
[  157.744767]  [<ffffffff810ea4ad>] ?  debug_lockdep_rcu_enabled+0x1d/0x20
[  157.744769]  [<ffffffff811fe09e>] do_vfs_ioctl+0x8e/0x680
[  157.744770]  [<ffffffff811a2377>] ? __might_fault+0x87/0x90
[  157.744771]  [<ffffffff811a232e>] ? __might_fault+0x3e/0x90
[  157.744773]  [<ffffffff810d3df2>] ?  trace_hardirqs_on_caller+0x122/0x1b0
[  157.744774]  [<ffffffff811fe6cc>] SyS_ioctl+0x3c/0x70
[  157.744776]  [<ffffffff8180fe69>] entry_SYSCALL_64_fastpath+0x1c/0xac

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97491
Fixes: 87660502f1a4 ("drm/i915/gen6+: Interpret mailbox error flags")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Lyude <cpaul@redhat.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://patchwork.freedesktop.org/patch/msgid/20160826105926.3413-1-chris@chris-wilson.co.uk
Acked-by: Mika Kuoppala <mika.kuoppala@intel.com>
mattmacy pushed a commit that referenced this issue Dec 29, 2016
Use 1UL for unsigned long, or we'll meet a overflow issue with UBSAN.

[   15.589489] UBSAN: Undefined behaviour in drivers/gpu/drm/drm_hashtab.c:145:35
[   15.589500] signed integer overflow:
[   15.589999] -2147483648 - 1 cannot be represented in type 'int'
[   15.590434] CPU: 2 PID: 294 Comm: plymouthd Not tainted 3.10.0-327.28.3.el7.x86_64 #1
[   15.590653] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 01/07/2011
[   15.591001]  1ffff1000670fe83 000000000d6b385e ffff88003387f3e0 ffffffff81ee3140
[   15.591028]  ffff88003387f3f8 ffffffff81ee31fd ffffffffa032f460 ffff88003387f560
[   15.591044]  ffffffff81ee46e2 0000002d00000009 0000000000000001 0000000041b58ab3
[   15.591059] Call Trace:
[   15.591078]  [<ffffffff81ee3140>] dump_stack+0x1e/0x20
[   15.591093]  [<ffffffff81ee31fd>] ubsan_epilogue+0x12/0x55
[   15.591109]  [<ffffffff81ee46e2>] handle_overflow+0x1ba/0x215
[   15.591126]  [<ffffffff81ee4528>] ? __ubsan_handle_negate_overflow+0x162/0x162
[   15.591146]  [<ffffffff8103416c>] ? print_context_stack+0x9c/0x160
[   15.591163]  [<ffffffff81031df2>] ? dump_trace+0x252/0x750
[   15.591181]  [<ffffffff81739023>] ? __list_add+0x93/0x160
[   15.591197]  [<ffffffff81ee4798>] __ubsan_handle_sub_overflow+0x2a/0x31
[   15.591261]  [<ffffffffa0282140>] drm_ht_just_insert_please+0x1e0/0x200 [drm]
[   15.591290]  [<ffffffffa0528c7a>] ttm_base_object_init+0x10a/0x270 [ttm]
[   15.591316]  [<ffffffffa052a34c>] ttm_vt_lock+0x28c/0x3a0 [ttm]
[   15.591343]  [<ffffffffa052a0c0>] ? ttm_write_lock+0x180/0x180 [ttm]
[   15.591362]  [<ffffffff81419526>] ? kasan_unpoison_shadow+0x36/0x50
[   15.591379]  [<ffffffff81419526>] ? kasan_unpoison_shadow+0x36/0x50
[   15.591396]  [<ffffffff81419526>] ? kasan_unpoison_shadow+0x36/0x50
[   15.591413]  [<ffffffff81419526>] ? kasan_unpoison_shadow+0x36/0x50
[   15.591442]  [<ffffffffa061cbe1>] vmw_master_set+0x121/0x470 [vmwgfx]
[   15.591459]  [<ffffffff811773a5>] ? __init_waitqueue_head+0x45/0x70
[   15.591487]  [<ffffffffa061cac0>] ? vmw_master_drop+0x310/0x310 [vmwgfx]
[   15.591535]  [<ffffffffa026946a>] drm_open+0x92a/0xc00 [drm]
[   15.591563]  [<ffffffffa0619ff0>] ? vmw_driver_open+0x170/0x170 [vmwgfx]
[   15.591610]  [<ffffffffa0268b40>] ? drm_poll+0xe0/0xe0 [drm]
[   15.591661]  [<ffffffffa02797b4>] drm_stub_open+0x224/0x330 [drm]
[   15.591711]  [<ffffffffa0279590>] ? drm_minor_acquire+0x240/0x240 [drm]
[   15.591727]  [<ffffffff8145fa8a>] chrdev_open+0x1fa/0x3f0
[   15.591742]  [<ffffffff8145f890>] ? cdev_put+0x50/0x50
[   15.591761]  [<ffffffff814f6dc3>] ? __fsnotify_parent+0x53/0x210
[   15.591778]  [<ffffffff8144fde1>] do_dentry_open+0x351/0x670
[   15.591792]  [<ffffffff8145f890>] ? cdev_put+0x50/0x50
[   15.591807]  [<ffffffff814503c2>] vfs_open+0xa2/0x170
[   15.591824]  [<ffffffff8147b5df>] do_last+0xccf/0x2c80
[   15.591842]  [<ffffffff8147a910>] ? filename_create+0x320/0x320
[   15.591858]  [<ffffffff81472549>] ? path_init+0x1b9/0xa90
[   15.591875]  [<ffffffff81472390>] ? mountpoint_last+0x9a0/0x9a0
[   15.591894]  [<ffffffff815f9ccf>] ? selinux_file_alloc_security+0xcf/0x130
[   15.591911]  [<ffffffff8147d777>] path_openat+0x1e7/0xcc0
[   15.591927]  [<ffffffff81031df2>] ? dump_trace+0x252/0x750
[   15.591943]  [<ffffffff8147d590>] ? do_last+0x2c80/0x2c80
[   15.591959]  [<ffffffff81739023>] ? __list_add+0x93/0x160
[   15.591974]  [<ffffffff8104b48d>] ? save_stack_trace+0x7d/0xb0
[   15.591989]  [<ffffffff81480824>] do_filp_open+0xa4/0x160
[   15.592004]  [<ffffffff81480780>] ? user_path_mountpoint_at+0x50/0x50
[   15.592022]  [<ffffffff8149d755>] ? __alloc_fd+0x175/0x300
[   15.592039]  [<ffffffff81453127>] do_sys_open+0x1b7/0x3f0
[   15.592054]  [<ffffffff81452f70>] ? filp_open+0x80/0x80
[   15.592070]  [<ffffffff81453392>] SyS_open+0x32/0x40
[   15.592088]  [<ffffffff81f08989>] system_call_fastpath+0x16/0x1b

Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com>
[seanpaul tweaked subject to remove "gpu/"]
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1473152138-25335-1-git-send-email-xiexiuqi@huawei.com
mattmacy pushed a commit that referenced this issue Dec 30, 2016
During rpm resume we restore the fences, but we do not have the
protection of struct_mutex. This rules out updating the activity
tracking on the fences, and requires us to rely on the rpm as the
serialisation barrier instead.

[  350.298052] [drm:intel_runtime_resume [i915]] Resuming device
[  350.308606]
[  350.310520] ===============================
[  350.315560] [ INFO: suspicious RCU usage. ]
[  350.320554] 4.8.0-rc8-bsw-rapl+ #3133 Tainted: G     U  W
[  350.327208] -------------------------------
[  350.331977] ../drivers/gpu/drm/i915/i915_gem_request.h:371 suspicious rcu_dereference_protected() usage!
[  350.342619]
[  350.342619] other info that might help us debug this:
[  350.342619]
[  350.351593]
[  350.351593] rcu_scheduler_active = 1, debug_locks = 0
[  350.358952] 3 locks held by Xorg/320:
[  350.363077]  #0:  (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa030589c>] drm_modeset_lock_all+0x3c/0xd0 [drm]
[  350.375162]  #1:  (crtc_ww_class_acquire){+.+.+.}, at: [<ffffffffa03058a6>] drm_modeset_lock_all+0x46/0xd0 [drm]
[  350.387022]  #2:  (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffa0305056>] drm_modeset_lock+0x36/0x110 [drm]
[  350.398236]
[  350.398236] stack backtrace:
[  350.403196] CPU: 1 PID: 320 Comm: Xorg Tainted: G     U  W       4.8.0-rc8-bsw-rapl+ #3133
[  350.412457] Hardware name: Intel Corporation CHERRYVIEW C0 PLATFORM/Braswell CRB, BIOS BRAS.X64.X088.R00.1510270350 10/27/2015
[  350.425212]  0000000000000000 ffff8801680a78c8 ffffffff81332187 ffff88016c5c5000
[  350.433611]  0000000000000001 ffff8801680a78f8 ffffffff810ca6da ffff88016cc8b0f0
[  350.442012]  ffff88016cc80000 ffff88016cc80000 ffff880177ad0000 ffff8801680a7948
[  350.450409] Call Trace:
[  350.453165]  [<ffffffff81332187>] dump_stack+0x67/0x90
[  350.458931]  [<ffffffff810ca6da>] lockdep_rcu_suspicious+0xea/0x120
[  350.466002]  [<ffffffffa039e8dd>] fence_update+0xbd/0x670 [i915]
[  350.472766]  [<ffffffffa039efe2>] i915_gem_restore_fences+0x52/0x70 [i915]
[  350.480496]  [<ffffffffa0368f42>] vlv_resume_prepare+0x72/0x570 [i915]
[  350.487839]  [<ffffffffa0369802>] intel_runtime_resume+0x102/0x210 [i915]
[  350.495442]  [<ffffffff8137f26f>] pci_pm_runtime_resume+0x7f/0xb0
[  350.502274]  [<ffffffff8137f1f0>] ? pci_restore_standard_config+0x40/0x40
[  350.509883]  [<ffffffff814401c5>] __rpm_callback+0x35/0x70
[  350.516037]  [<ffffffff8137f1f0>] ? pci_restore_standard_config+0x40/0x40
[  350.523646]  [<ffffffff81440224>] rpm_callback+0x24/0x80
[  350.529604]  [<ffffffff8137f1f0>] ? pci_restore_standard_config+0x40/0x40
[  350.537212]  [<ffffffff814417bd>] rpm_resume+0x4ad/0x740
[  350.543161]  [<ffffffff81441aa1>] __pm_runtime_resume+0x51/0x80
[  350.549824]  [<ffffffffa03889c8>] intel_runtime_pm_get+0x28/0x90 [i915]
[  350.557265]  [<ffffffffa0388a53>] intel_display_power_get+0x23/0x50 [i915]
[  350.565001]  [<ffffffffa03ef23d>] intel_atomic_commit_tail+0xdfd/0x10b0 [i915]
[  350.573106]  [<ffffffffa034b2e9>] ? drm_atomic_helper_swap_state+0x159/0x300 [drm_kms_helper]
[  350.582659]  [<ffffffff81615091>] ? _raw_spin_unlock+0x31/0x50
[  350.589205]  [<ffffffffa034b2e9>] ? drm_atomic_helper_swap_state+0x159/0x300 [drm_kms_helper]
[  350.598787]  [<ffffffffa03ef8a5>] intel_atomic_commit+0x3b5/0x500 [i915]
[  350.606319]  [<ffffffffa03061dc>] ? drm_atomic_set_crtc_for_connector+0xcc/0x100 [drm]
[  350.615209]  [<ffffffffa0306b49>] drm_atomic_commit+0x49/0x50 [drm]
[  350.622242]  [<ffffffffa034dee8>] drm_atomic_helper_set_config+0x88/0xc0 [drm_kms_helper]
[  350.631419]  [<ffffffffa02f94ac>] drm_mode_set_config_internal+0x6c/0x120 [drm]
[  350.639623]  [<ffffffffa02fa94c>] drm_mode_setcrtc+0x22c/0x4d0 [drm]
[  350.646760]  [<ffffffffa02f0f19>] drm_ioctl+0x209/0x460 [drm]
[  350.653217]  [<ffffffffa02fa720>] ? drm_mode_getcrtc+0x150/0x150 [drm]
[  350.660536]  [<ffffffff810c984a>] ? __lock_is_held+0x4a/0x70
[  350.666885]  [<ffffffff81202303>] do_vfs_ioctl+0x93/0x6b0
[  350.672939]  [<ffffffff8120f843>] ? __fget+0x113/0x200
[  350.678797]  [<ffffffff8120f735>] ? __fget+0x5/0x200
[  350.684361]  [<ffffffff81202964>] SyS_ioctl+0x44/0x80
[  350.690030]  [<ffffffff81001deb>] do_syscall_64+0x5b/0x120
[  350.696184]  [<ffffffff81615ada>] entry_SYSCALL64_slow_path+0x25/0x25

Note we also have to remember the lesson from commit 4fc788f5ee3d
("drm/i915: Flush delayed fence releases after reset") where we have to
flush any changes to the fence on restore.

v2: Replace call to release user mmaps with an assertion that they have
already been zapped.

Fixes: 49ef5294cda2 ("drm/i915: Move fence tracking from object to vma")
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161012114827.17031-1-chris@chris-wilson.co.uk
(cherry picked from commit 4676dc838b37ed8c6f3da4571cb4a04cbd604801)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
johalun pushed a commit that referenced this issue Apr 5, 2017
In the error path, we have to be ready to handle an error before either
the state or restore_state have been allocated.

[  397.001342] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  397.001419] IP: [<ffffffffa04347b4>] intel_get_load_detect_pipe+0xe4/0x610 [i915]
[  397.001502] PGD 136a2a067
[  397.001523] PUD 134b5f067
[  397.001546] PMD 0

[  397.001569] Oops: 0002 [#1] PREEMPT SMP
[  397.001599] Modules linked in: snd_hda_intel i915 cdc_ncm usbnet mii x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core snd_pcm lpc_ich mei_me mei sdhci_pci sdhci mmc_core e1000e ptp pps_core [last unloaded: i915]
[  397.001902] CPU: 1 PID: 9287 Comm: kms_force_conne Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1730+ #1
[  397.001965] Hardware name: LENOVO 2356GCG/2356GCG, BIOS G7ET31WW (1.13 ) 07/02/2012
[  397.002017] task: ffff880138c38040 task.stack: ffffc900083e4000
[  397.002057] RIP: 0010:[<ffffffffa04347b4>]  [<ffffffffa04347b4>] intel_get_load_detect_pipe+0xe4/0x610 [i915]
[  397.002153] RSP: 0018:ffffc900083e7ae8  EFLAGS: 00010286
[  397.002191] RAX: 00000000ffffffdd RBX: ffffc900083e7bc8 RCX: 0000000000000006
[  397.002239] RDX: 0000000000000006 RSI: ffff880138c388b8 RDI: ffffc900083e79e0
[  397.002287] RBP: ffffc900083e7b78 R08: 0000000000000000 R09: 0000000000000000
[  397.002335] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[  397.002386] R13: ffff8801305e1158 R14: 00000000ffffffdd R15: 0000000000000000
[  397.002434] FS:  00007fea1b03c740(0000) GS:ffff88013e240000(0000) knlGS:0000000000000000
[  397.002488] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  397.002528] CR2: 0000000000000000 CR3: 00000001361da000 CR4: 00000000001406e0
[  397.002576] Stack:
[  397.002592]  ffff88013046f180 0000000000000000 ffffc900083e7bc0 0000000000000000
[  397.002655]  0000000000000000 ffff8801306bd038 ffff88012e980000 ffffc90000000001
[  397.002718]  ffffc90000000000 ffff880136b8ca88 ffff88012e980890 ffff88012e980540
[  397.002780] Call Trace:
[  397.002828]  [<ffffffffa044e8c4>] intel_crt_detect+0x3c4/0x8f0 [i915]
[  397.002876]  [<ffffffff810e37fa>] ? vprintk_default+0x1a/0x20
[  397.002918]  [<ffffffff8116eb68>] ? printk+0x43/0x4b
[  397.002956]  [<ffffffff81546b06>] drm_helper_probe_single_connector_modes+0x406/0x4f0
[  397.003014]  [<ffffffff81819c09>] ? mutex_unlock+0x9/0x10
[  397.003054]  [<ffffffff815723dc>] drm_mode_getconnector+0x33c/0x3c0
[  397.003099]  [<ffffffff810ed59d>] ? debug_lockdep_rcu_enabled+0x1d/0x20
[  397.003147]  [<ffffffff811a6bae>] ? __might_fault+0x3e/0x90
[  397.003191]  [<ffffffff8155aaf6>] drm_ioctl+0x1f6/0x480
[  397.003231]  [<ffffffff815720a0>] ? drm_mode_connector_property_set_ioctl+0x30/0x30
[  397.003285]  [<ffffffff8120308e>] do_vfs_ioctl+0x8e/0x690
[  397.003324]  [<ffffffff810a102c>] ? task_work_run+0x8c/0xb0
[  397.003366]  [<ffffffff810d6d92>] ? trace_hardirqs_on_caller+0x122/0x1b0
[  397.003412]  [<ffffffff812036cc>] SyS_ioctl+0x3c/0x70
[  397.003451]  [<ffffffff8181df2e>] entry_SYSCALL_64_fastpath+0x1c/0xb1
[  397.003496] Code: 85 c0 41 89 c6 75 57 49 8b 85 f0 00 00 00 48 89 de 45 31 ff 48 8d 78 20 e8 1a 89 13 e1 45 31 c9 85 c0 41 89 c6 0f 84 2f 01 00 00 <f0> 41 83 29 01 74 53 f0 41 83 2f 01 74 2d 41 83 fe dd 75 35 48
[  397.003837] RIP  [<ffffffffa04347b4>] intel_get_load_detect_pipe+0xe4/0x610 [i915]
[  397.003921]  RSP <ffffc900083e7ae8>
[  397.003947] CR2: 0000000000000000

Testcase: igt/kms_force_connector_basic/force-load-detect # ivb-3720m
Fixes: 0853695c3ba4 ("drm: Add reference counting to drm_atomic_state"
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161019113743.19847-1-chris@chris-wilson.co.uk
markjdb pushed a commit to markjdb/freebsd-base-graphics that referenced this issue Apr 19, 2017
FreeBSD's DTS contained only one PL050 node and driver considered it to
be PS/2 keyboard. In reality PL050 is a PS/2 port that pushes bytes to/from
the periphers connected to it. New DTS contains two nodes and QEMU emulates
keyboard connected to port #0 and mouse connected to port FreeBSDDesktop#1. Since there
is no way to say what's connected to port by checking DTS we hardcode
this knowledge in the driver: it assumes keyboard on port #0 and ignores
port FreeBSDDesktop#1 altogether.

Also QEMU defaults emulated keyboard to scan code set 2 while driver used
to work with scan code set 1 so when initializing driver make sure keyboard
is switched to scan code set 1
johalun pushed a commit that referenced this issue Apr 24, 2017
The breadcrumbs are about to be used from within IRQ context sections
(e.g. nouveau signals a fence from an interrupt handler causing us to
submit a new request) and/or from bottom-half tasklets (i.e.
intel_lrc_irq_handler), therefore we need to employ the irqsafe spinlock
variants.

For example, deferring the request submission to the
intel_lrc_irq_handler generates this trace:

[   66.388639] =================================
[   66.388650] [ INFO: inconsistent lock state ]
[   66.388663] 4.9.0-rc2+ #56 Not tainted
[   66.388672] ---------------------------------
[   66.388682] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[   66.388695] swapper/1/0 [HC0[0]:SC1[1]:HE0:SE0] takes:
[   66.388706]  (&(&b->lock)->rlock){+.?...} , at: [<ffffffff81401c88>] intel_engine_enable_signaling+0x78/0x150
[   66.388761] {SOFTIRQ-ON-W} state was registered at:
[   66.388772]   [   66.388783] [<ffffffff810bd842>] __lock_acquire+0x682/0x1870
[   66.388795]   [   66.388803] [<ffffffff810bedbc>] lock_acquire+0x6c/0xb0
[   66.388814]   [   66.388824] [<ffffffff8161753a>] _raw_spin_lock+0x2a/0x40
[   66.388835]   [   66.388845] [<ffffffff81401e41>] intel_engine_reset_breadcrumbs+0x21/0xb0
[   66.388857]   [   66.388866] [<ffffffff81403ae7>] gen8_init_common_ring+0x67/0x100
[   66.388878]   [   66.388887] [<ffffffff81403b92>] gen8_init_render_ring+0x12/0x60
[   66.388903]   [   66.388912] [<ffffffff813f8707>] i915_gem_init_hw+0xf7/0x2a0
[   66.388927]   [   66.388936] [<ffffffff813f899b>] i915_gem_init+0xbb/0xf0
[   66.388950]   [   66.388959] [<ffffffff813b4980>] i915_driver_load+0x7e0/0x1330
[   66.388978]   [   66.388988] [<ffffffff813c09d8>] i915_pci_probe+0x28/0x40
[   66.389003]   [   66.389013] [<ffffffff812fa0db>] pci_device_probe+0x8b/0xf0
[   66.389028]   [   66.389037] [<ffffffff8147737e>] driver_probe_device+0x21e/0x430
[   66.389056]   [   66.389065] [<ffffffff8147766e>] __driver_attach+0xde/0xe0
[   66.389080]   [   66.389090] [<ffffffff814751ad>] bus_for_each_dev+0x5d/0x90
[   66.389105]   [   66.389113] [<ffffffff81477799>] driver_attach+0x19/0x20
[   66.389134]   [   66.389144] [<ffffffff81475ced>] bus_add_driver+0x15d/0x260
[   66.389159]   [   66.389168] [<ffffffff81477e3b>] driver_register+0x5b/0xd0
[   66.389183]   [   66.389281] [<ffffffff812fa19b>] __pci_register_driver+0x5b/0x60
[   66.389301]   [   66.389312] [<ffffffff81aed333>] i915_init+0x3e/0x45
[   66.389326]   [   66.389336] [<ffffffff81ac2ffa>] do_one_initcall+0x8b/0x118
[   66.389350]   [   66.389359] [<ffffffff81ac323a>] kernel_init_freeable+0x1b3/0x23b
[   66.389378]   [   66.389387] [<ffffffff8160fc39>] kernel_init+0x9/0x100
[   66.389402]   [   66.389411] [<ffffffff816180e7>] ret_from_fork+0x27/0x40
[   66.389426] irq event stamp: 315865
[   66.389438] hardirqs last  enabled at (315864): [<ffffffff816178f1>] _raw_spin_unlock_irqrestore+0x31/0x50
[   66.389469] hardirqs last disabled at (315865): [<ffffffff816176b3>] _raw_spin_lock_irqsave+0x13/0x50
[   66.389499] softirqs last  enabled at (315818): [<ffffffff8107a04c>] _local_bh_enable+0x1c/0x50
[   66.389530] softirqs last disabled at (315819): [<ffffffff8107a50e>] irq_exit+0xbe/0xd0
[   66.389559]
[   66.389559] other info that might help us debug this:
[   66.389580]  Possible unsafe locking scenario:
[   66.389580]
[   66.389598]        CPU0
[   66.389609]        ----
[   66.389620]   lock(&(&b->lock)->rlock);
[   66.389650]   <Interrupt>
[   66.389661]     lock(&(&b->lock)->rlock);
[   66.389690]
[   66.389690]  *** DEADLOCK ***
[   66.389690]
[   66.389715] 2 locks held by swapper/1/0:
[   66.389728]  #0: (&(&tl->lock)->rlock){..-...}, at: [<ffffffff81403e01>] intel_lrc_irq_handler+0x201/0x3c0
[   66.389785]  #1: (&(&req->lock)->rlock/1){..-...}, at: [<ffffffff813fc0af>] __i915_gem_request_submit+0x8f/0x170
[   66.389854]
[   66.389854] stack backtrace:
[   66.389959] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.9.0-rc2+ #56
[   66.389976] Hardware name:                  /        , BIOS PYBSWCEL.86A.0027.2015.0507.1758 05/07/2015
[   66.389999]  ffff88027fd03c58 ffffffff812beae5 ffff88027696e680 ffffffff822afe20
[   66.390036]  ffff88027fd03ca8 ffffffff810bb420 0000000000000001 0000000000000000
[   66.390070]  0000000000000000 0000000000000006 0000000000000004 ffff88027696ee10
[   66.390104] Call Trace:
[   66.390117]  <IRQ>
[   66.390128]  [<ffffffff812beae5>] dump_stack+0x68/0x93
[   66.390147]  [<ffffffff810bb420>] print_usage_bug+0x1d0/0x1e0
[   66.390164]  [<ffffffff810bb8a0>] mark_lock+0x470/0x4f0
[   66.390181]  [<ffffffff810ba9d0>] ? print_shortest_lock_dependencies+0x1b0/0x1b0
[   66.390203]  [<ffffffff810bd75d>] __lock_acquire+0x59d/0x1870
[   66.390221]  [<ffffffff810bedbc>] lock_acquire+0x6c/0xb0
[   66.390237]  [<ffffffff810bedbc>] ? lock_acquire+0x6c/0xb0
[   66.390255]  [<ffffffff81401c88>] ? intel_engine_enable_signaling+0x78/0x150
[   66.390273]  [<ffffffff8161753a>] _raw_spin_lock+0x2a/0x40
[   66.390291]  [<ffffffff81401c88>] ? intel_engine_enable_signaling+0x78/0x150
[   66.390309]  [<ffffffff81401c88>] intel_engine_enable_signaling+0x78/0x150
[   66.390327]  [<ffffffff813fc170>] __i915_gem_request_submit+0x150/0x170
[   66.390345]  [<ffffffff81403e8b>] intel_lrc_irq_handler+0x28b/0x3c0
[   66.390363]  [<ffffffff81079d97>] tasklet_action+0x57/0xc0
[   66.390380]  [<ffffffff8107a249>] __do_softirq+0x119/0x240
[   66.390396]  [<ffffffff8107a50e>] irq_exit+0xbe/0xd0
[   66.390414]  [<ffffffff8101afd5>] do_IRQ+0x65/0x110
[   66.390431]  [<ffffffff81618806>] common_interrupt+0x86/0x86
[   66.390446]  <EOI>
[   66.390457]  [<ffffffff814ec6d1>] ? cpuidle_enter_state+0x151/0x200
[   66.390480]  [<ffffffff814ec7a2>] cpuidle_enter+0x12/0x20
[   66.390498]  [<ffffffff810b639e>] call_cpuidle+0x1e/0x40
[   66.390516]  [<ffffffff810b65ae>] cpu_startup_entry+0x10e/0x1f0
[   66.390534]  [<ffffffff81036133>] start_secondary+0x103/0x130

(This is split out of the defer global seqno allocation patch due to
realisation that we need a more complete conversion if we want to defer
request submission even further.)

v2: lockdep was warning about mixed SOFTIRQ contexts not HARDIRQ
contexts so we only need to use spin_lock_bh and not disable interrupts.

v3: We need full irq protection as we may be called from a third party
interrupt handler (via fences).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-32-chris@chris-wilson.co.uk
johalun pushed a commit that referenced this issue May 1, 2017
As we may allocate from within the obj->mm.lock we may enter the
shrinker for direct reclaim. Operating on the current object is
prevented by checking for obj->mm.pages (which is only set as the last
operation in the allocation path). However, we need to identify the
single recursion of accessing another object's obj->mm.lock as the two
locks have identical class and so appear to be the same to lockdep,
convincing it that a deadlock is possible. Use mutex_lock_nested() to
remove the false positive.

[ 2165.945734] =================================
[ 2165.945749] [ INFO: inconsistent lock state ]
[ 2165.945765] 4.9.0-rc2+ #2 Tainted: G        W
[ 2165.945781] ---------------------------------
[ 2165.945796] inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
[ 2165.945816] kswapd0/62 [HC0[0]:SC0[0]:HE1:SE1] takes: (&obj->mm.lock){+.+.?.}, at: [<ffffffffc0289a1f>] i915_gem_shrink+0x29f/0x500 [i915]
[ 2165.945904] {RECLAIM_FS-ON-W} state was registered at:
[ 2165.945931] [<ffffffffb10bd50f>] mark_held_locks+0x6f/0xa0
[ 2165.945956] [<ffffffffb10bf889>] lockdep_trace_alloc+0x69/0xc0
[ 2165.945982] [<ffffffffb11eea53>] kmem_cache_alloc_trace+0x33/0x2a0
[ 2165.946019] [<ffffffffc028a28a>] i915_gem_object_get_pages_stolen+0x6a/0xd0 [i915]
[ 2165.946060] [<ffffffffc027e1d0>] ____i915_gem_object_get_pages+0x20/0x60 [i915]
[ 2165.946098] [<ffffffffc027e268>] __i915_gem_object_get_pages+0x58/0x70 [i915]
[ 2165.946138] [<ffffffffc028a3dc>] _i915_gem_object_create_stolen+0xec/0x120 [i915]
[ 2165.946177] [<ffffffffc028af73>] i915_gem_object_create_stolen_for_preallocated+0xf3/0x3f0 [i915]
[ 2165.946222] [<ffffffffc02bae43>] intel_alloc_initial_plane_obj.isra.125+0xd3/0x200 [i915]
[ 2165.946266] [<ffffffffc02cb1c1>] intel_modeset_init+0x931/0x1530 [i915]
[ 2165.946301] [<ffffffffc023d584>] i915_driver_load+0xa14/0x14a0 [i915]
[ 2165.946335] [<ffffffffc0248aff>] i915_pci_probe+0x4f/0x70 [i915]
[ 2165.946362] [<ffffffffb13cc452>] local_pci_probe+0x42/0xa0
[ 2165.946386] [<ffffffffb13cd903>] pci_device_probe+0x103/0x150
[ 2165.946411] [<ffffffffb14adeb3>] driver_probe_device+0x223/0x430
[ 2165.946436] [<ffffffffb14ae1a3>] __driver_attach+0xe3/0xf0
[ 2165.946461] [<ffffffffb14ab943>] bus_for_each_dev+0x73/0xc0
[ 2165.946485] [<ffffffffb14ad5ee>] driver_attach+0x1e/0x20
[ 2165.946508] [<ffffffffb14ad003>] bus_add_driver+0x173/0x270
[ 2165.946533] [<ffffffffb14aee70>] driver_register+0x60/0xe0
[ 2165.946557] [<ffffffffb13cbd6d>] __pci_register_driver+0x5d/0x60
[ 2165.946606] [<ffffffffc0378057>] soundcore_open+0x17/0x230 [soundcore]
[ 2165.946636] [<ffffffffb1000450>] do_one_initcall+0x50/0x180
[ 2165.946661] [<ffffffffb117fd2d>] do_init_module+0x5f/0x1f1
[ 2165.946685] [<ffffffffb1108964>] load_module+0x2174/0x2a80
[ 2165.946709] [<ffffffffb11094df>] SYSC_finit_module+0xdf/0x110
[ 2165.946734] [<ffffffffb110952e>] SyS_finit_module+0xe/0x10
[ 2165.946758] [<ffffffffb1742aea>] entry_SYSCALL_64_fastpath+0x18/0xad
[ 2165.946776] irq event stamp: 90871
[ 2165.946788] hardirqs last  enabled at (90871):
[ 2165.946805] [<ffffffffb173e9da>] __mutex_unlock_slowpath+0x11a/0x1c0
[ 2165.946823] hardirqs last disabled at (90870):
[ 2165.946839] [<ffffffffb173e91b>] __mutex_unlock_slowpath+0x5b/0x1c0
[ 2165.946856] softirqs last  enabled at (90858):
[ 2165.946872] [<ffffffffb174581a>] __do_softirq+0x39a/0x4c6
[ 2165.946887] softirqs last disabled at (90671):
[ 2165.946902] [<ffffffffb1066cea>] irq_exit+0xea/0xf0
[ 2165.946916] other info that might help us debug this:
[ 2165.946936]  Possible unsafe locking scenario:
[ 2165.946955]        CPU0
[ 2165.946965]        ----
[ 2165.946975]   lock(&obj->mm.lock);
[ 2165.947000]   <Interrupt>
[ 2165.947010]     lock(&obj->mm.lock);
[ 2165.947035] *** DEADLOCK ***
[ 2165.947054] 2 locks held by kswapd0/62:
[ 2165.947067]  #0: (shrinker_rwsem){++++..}, at: [<ffffffffb119a20e>] shrink_slab.part.40+0x5e/0x5d0
[ 2165.947120]  #1: (&dev->struct_mutex){+.+.+.}, at: [<ffffffffc028954b>] i915_gem_shrinker_lock+0x1b/0x60 [i915]
[ 2165.948909] stack backtrace:
[ 2165.950650] CPU: 2 PID: 62 Comm: kswapd0 Tainted: G        W 4.9.0-rc2+ #2
[ 2165.951587] Hardware name: LENOVO 80MX/Lenovo E31-80, BIOS DCCN34WW(V2.03) 12/01/2015
[ 2165.952484]  ffffc90000b5f8c8 ffffffffb137f645 ffff88016c5a2700 ffffffffb25f20a0
[ 2165.953395]  ffffc90000b5f918 ffffffffb10bcecd 0000000000000000 ffff880100000001
[ 2165.954305]  0000000000000001 000000000000000a ffff88016c5a2fd0 ffff88016c5a2700
[ 2165.955240] Call Trace:
[ 2165.956170]  [<ffffffffb137f645>] dump_stack+0x68/0x93
[ 2165.957071]  [<ffffffffb10bcecd>] print_usage_bug+0x1dd/0x1f0
[ 2165.957979]  [<ffffffffb10bd439>] mark_lock+0x559/0x5c0
[ 2165.958875]  [<ffffffffb10bc3f0>] ?  print_shortest_lock_dependencies+0x1b0/0x1b0
[ 2165.959829]  [<ffffffffb10be04d>] __lock_acquire+0x66d/0x12a0
[ 2165.960729]  [<ffffffffb11ef541>] ? __slab_free+0xa1/0x340
[ 2165.961625]  [<ffffffffb10dba5d>] ?  debug_lockdep_rcu_enabled+0x1d/0x20
[ 2165.962530]  [<ffffffffb10bd50f>] ? mark_held_locks+0x6f/0xa0
[ 2165.963457]  [<ffffffffb10bf0b0>] lock_acquire+0xf0/0x1f0
[ 2165.964368]  [<ffffffffc0289a1f>] ? i915_gem_shrink+0x29f/0x500 [i915]
[ 2165.965269]  [<ffffffffc0289a1f>] ? i915_gem_shrink+0x29f/0x500 [i915]
[ 2165.966150]  [<ffffffffb173d837>] mutex_lock_nested+0x77/0x420
[ 2165.967030]  [<ffffffffc0289a1f>] ? i915_gem_shrink+0x29f/0x500 [i915]
[ 2165.967952]  [<ffffffffc027c7a1>] ?  __i915_gem_object_put_pages.part.58+0x161/0x1b0 [i915]
[ 2165.968835]  [<ffffffffc0289a1f>] i915_gem_shrink+0x29f/0x500 [i915]
[ 2165.969712]  [<ffffffffc0289e40>] i915_gem_shrinker_scan+0x70/0xb0 [i915]
[ 2165.970591]  [<ffffffffb119a3ae>] shrink_slab.part.40+0x1fe/0x5d0
[ 2165.971504]  [<ffffffffb119f19c>] shrink_node+0x22c/0x320
[ 2165.972371]  [<ffffffffb11a05fb>] kswapd+0x38b/0x9b0
[ 2165.973238]  [<ffffffffb11a0270>] ?  mem_cgroup_shrink_node+0x330/0x330
[ 2165.974068]  [<ffffffffb108630f>] kthread+0xff/0x120
[ 2165.974929]  [<ffffffffb1086210>] ? kthread_park+0x60/0x60
[ 2165.975847]  [<ffffffffb1742d57>] ret_from_fork+0x27/0x40

Reported-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: 1233e2db199d ("drm/i915: Move object backing storage manipulation...")
Testcase: igt/gem_ctx_create/maximum-swap
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161031124048.30355-1-chris@chris-wilson.co.uk
johalun pushed a commit that referenced this issue May 1, 2017
To flush all call_rcu() tasks (here from i915_gem_free_object()) we need
to call rcu_barrier() (not synchronize_rcu()). If we don't then we may
still have objects being freed as we continue to teardown the driver -
in particular, the recently released rings may race with the memory
manager shutdown resulting in sporadic:

[  142.217186] WARNING: CPU: 7 PID: 6185 at drivers/gpu/drm/drm_mm.c:932 drm_mm_takedown+0x2e/0x40
[  142.217187] Memory manager not clean during takedown.
[  142.217187] Modules linked in: i915(-) x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic mei_me mei snd_hda_codec_hdmi snd_hda_codec snd_hwdep snd_hda_core snd_pcm e1000e ptp pps_core [last unloaded: snd_hda_intel]
[  142.217199] CPU: 7 PID: 6185 Comm: rmmod Not tainted 4.9.0-rc2-CI-Trybot_242+ #1
[  142.217199] Hardware name: LENOVO 10AGS00601/SHARKBAY, BIOS FBKT34AUS 04/24/2013
[  142.217200]  ffffc90002ecfce0 ffffffff8142dd65 ffffc90002ecfd30 0000000000000000
[  142.217202]  ffffc90002ecfd20 ffffffff8107e4e6 000003a40778c2a8 ffff880401355c48
[  142.217204]  ffff88040778c2a8 ffffffffa040f3c0 ffffffffa040f4a0 00005621fbf8b1f0
[  142.217206] Call Trace:
[  142.217209]  [<ffffffff8142dd65>] dump_stack+0x67/0x92
[  142.217211]  [<ffffffff8107e4e6>] __warn+0xc6/0xe0
[  142.217213]  [<ffffffff8107e54a>] warn_slowpath_fmt+0x4a/0x50
[  142.217214]  [<ffffffff81559e3e>] drm_mm_takedown+0x2e/0x40
[  142.217236]  [<ffffffffa035c02a>] i915_gem_cleanup_stolen+0x1a/0x20 [i915]
[  142.217246]  [<ffffffffa034c581>] i915_ggtt_cleanup_hw+0x31/0xb0 [i915]
[  142.217253]  [<ffffffffa0310311>] i915_driver_cleanup_hw+0x31/0x40 [i915]
[  142.217260]  [<ffffffffa0312001>] i915_driver_unload+0x141/0x1a0 [i915]
[  142.217268]  [<ffffffffa031c2c4>] i915_pci_remove+0x14/0x20 [i915]
[  142.217269]  [<ffffffff8147d214>] pci_device_remove+0x34/0xb0
[  142.217271]  [<ffffffff8157b14c>] __device_release_driver+0x9c/0x150
[  142.217272]  [<ffffffff8157bcc6>] driver_detach+0xb6/0xc0
[  142.217273]  [<ffffffff8157abe3>] bus_remove_driver+0x53/0xd0
[  142.217274]  [<ffffffff8157c787>] driver_unregister+0x27/0x50
[  142.217276]  [<ffffffff8147c265>] pci_unregister_driver+0x25/0x70
[  142.217287]  [<ffffffffa03d764c>] i915_exit+0x1a/0x71 [i915]
[  142.217289]  [<ffffffff811136b3>] SyS_delete_module+0x193/0x1e0
[  142.217291]  [<ffffffff818174ae>] entry_SYSCALL_64_fastpath+0x1c/0xb1
[  142.217292] ---[ end trace 6fd164859c154772 ]---
[  142.217505] [drm:show_leaks] *ERROR* node [6b6b6b6b6b6b6b6b + 6b6b6b6b6b6b6b6b]: inserted at
                [<ffffffff81559ff3>] save_stack.isra.1+0x53/0xa0
                [<ffffffff8155a98d>] drm_mm_insert_node_in_range_generic+0x2ad/0x360
                [<ffffffffa035bf23>] i915_gem_stolen_insert_node_in_range+0x93/0xe0 [i915]
                [<ffffffffa035c855>] i915_gem_object_create_stolen+0x75/0xb0 [i915]
                [<ffffffffa036a51a>] intel_engine_create_ring+0x9a/0x140 [i915]
                [<ffffffffa036a921>] intel_init_ring_buffer+0xf1/0x440 [i915]
                [<ffffffffa036be1b>] intel_init_render_ring_buffer+0xab/0x1b0 [i915]
                [<ffffffffa0363d08>] intel_engines_init+0xc8/0x210 [i915]
                [<ffffffffa0355d7c>] i915_gem_init+0xac/0xf0 [i915]
                [<ffffffffa0311454>] i915_driver_load+0x9c4/0x1430 [i915]
                [<ffffffffa031c2f8>] i915_pci_probe+0x28/0x40 [i915]
                [<ffffffff8147d315>] pci_device_probe+0x85/0xf0
                [<ffffffff8157b7ff>] driver_probe_device+0x21f/0x430
                [<ffffffff8157baee>] __driver_attach+0xde/0xe0

In particular note that the node was being poisoned as we inspected the
list, a  clear indication that the object is being freed as we make the
assertion.

v2: Don't loop, just assert that we do all the work required as that
will be better at detecting further errors.

Fixes: fbbd37b36fa5 ("drm/i915: Move object release to a freelist + worker")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161101084843.3961-1-chris@chris-wilson.co.uk
johalun pushed a commit that referenced this issue May 1, 2017
If we have a tiled object and an unknown CPU swizzle pattern, we pin the
pages to prevent the object from being swapped out (and us corrupting
the contents as we do not know the access pattern and so cannot convert
it to linear and back to tiled on reuse). This requires us to remember
to drop the extra pinning when freeing the object, or else we trigger
warnings about the pin leak. In commit fbbd37b36fa5 ("drm/i915: Move
object release to a freelist + worker"), the object free path was
deferred to a worker, but the unpinning of the quirk, along with marking
the object as reclaimable, was left on the immediate path (so that if
required we could reclaim the pages under memory pressure as early as
possible). However, this split introduced a bug where the pages were no
longer being unpinned if they were marked as unneeded.

[  231.800401] WARNING: CPU: 1 PID: 90 at drivers/gpu/drm/i915/i915_gem.c:4275 __i915_gem_free_objects+0x326/0x3c0 [i915]
[  231.800403] WARN_ON(i915_gem_object_has_pinned_pages(obj))
[  231.800405] Modules linked in:
[  231.800406]  snd_hda_intel i915 snd_hda_codec_generic mei_me snd_hda_codec coretemp snd_hwdep mei lpc_ich snd_hda_core snd_pcm e1000e ptp pps_core [last unloaded: i915]
[  231.800426] CPU: 1 PID: 90 Comm: kworker/1:4 Tainted: G     U          4.9.0-rc2-CI-CI_DRM_1780+ #1
[  231.800428] Hardware name: LENOVO 7465CTO/7465CTO, BIOS 6DET44WW (2.08 ) 04/22/2009
[  231.800456] Workqueue: events __i915_gem_free_work [i915]
[  231.800459]  ffffc9000034fc80 ffffffff8142dd65 ffffc9000034fcd0 0000000000000000
[  231.800465]  ffffc9000034fcc0 ffffffff8107e4e6 000010b300000001 0000000000001000
[  231.800469]  ffff88011d3db740 ffff880130ef0000 0000000000000000 ffff880130ef5ea0
[  231.800474] Call Trace:
[  231.800479]  [<ffffffff8142dd65>] dump_stack+0x67/0x92
[  231.800484]  [<ffffffff8107e4e6>] __warn+0xc6/0xe0
[  231.800487]  [<ffffffff8107e54a>] warn_slowpath_fmt+0x4a/0x50
[  231.800491]  [<ffffffff811d12ac>] ? kmem_cache_free+0x2dc/0x340
[  231.800520]  [<ffffffffa009ef36>] __i915_gem_free_objects+0x326/0x3c0 [i915]
[  231.800548]  [<ffffffffa009effe>] __i915_gem_free_work+0x2e/0x50 [i915]
[  231.800552]  [<ffffffff8109c27c>] process_one_work+0x1ec/0x6b0
[  231.800555]  [<ffffffff8109c1f6>] ? process_one_work+0x166/0x6b0
[  231.800558]  [<ffffffff8109c789>] worker_thread+0x49/0x490
[  231.800561]  [<ffffffff8109c740>] ? process_one_work+0x6b0/0x6b0
[  231.800563]  [<ffffffff8109c740>] ? process_one_work+0x6b0/0x6b0
[  231.800566]  [<ffffffff810a2aab>] kthread+0xeb/0x110
[  231.800569]  [<ffffffff810a29c0>] ? kthread_park+0x60/0x60
[  231.800573]  [<ffffffff818164a7>] ret_from_fork+0x27/0x40

Moving to a separate flag for tracking the quirked pin is overkill for
the bug (since we only have to interchange the two tests in
i915_gem_free_object) but it does reduce a complicated test on all
objects and provide a sanitycheck for uncommon code paths.

Fixes: fbbd37b36fa5 ("drm/i915: Move object release to a freelist + worker")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161101100317.11129-2-chris@chris-wilson.co.uk
johalun pushed a commit that referenced this issue May 1, 2017
Currently, the vma is being unlink from the object lookup on destroy.
However, we are meant to be decoupling it upon close so that the user
cannot access the closed vma whilst it remains active on the GPU.

[   34.074858] kernel BUG at drivers/gpu/drm/i915/i915_gem_gtt.c:3561!
[   34.074875] invalid opcode: 0000 [#1] PREEMPT SMP
[   34.074888] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich mei_me mei snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep snd_hda_core i2c_designware_platform i2c_designware_core snd_pcm e1000e ptp pps_core sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
[   34.075010] CPU: 1 PID: 6224 Comm: gem_close_race Tainted: G     U          4.9.0-rc3-CI-CI_DRM_1800+ #1
[   34.075034] Hardware name:                  /NUC5i7RYB, BIOS RYBDWi35.86A.0355.2016.0224.1501 02/24/2016
[   34.075057] task: ffff8802459a8040 task.stack: ffffc90000524000
[   34.075074] RIP: 0010:[<ffffffffa0392cbc>]  [<ffffffffa0392cbc>] i915_gem_obj_lookup_or_create_vma+0x8c/0xc0 [i915]
[   34.075118] RSP: 0018:ffffc90000527b68  EFLAGS: 00010202
[   34.075135] RAX: ffff8802426c5e40 RBX: 0000000000000000 RCX: ffff8802447fc2a8
[   34.075158] RDX: 0000000000000000 RSI: ffff8802447fc2a8 RDI: ffff880248a4a880
[   34.075181] RBP: ffffc90000527b88 R08: 0000000000000008 R09: 0000000000000000
[   34.075203] R10: 0000000000000001 R11: 0000000000000000 R12: ffff880248a4a880
[   34.075225] R13: ffff8802447fc2a8 R14: ffff880243e9afa8 R15: ffff880248a4a9c8
[   34.075248] FS:  00007f9b43e59740(0000) GS:ffff880256c80000(0000) knlGS:0000000000000000
[   34.075273] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   34.075292] CR2: 00007f9b43419140 CR3: 000000024455d000 CR4: 00000000003406e0
[   34.075314] Stack:
[   34.075323]  0000000000000000 ffffc90000527bd0 ffff880243cb8008 ffff880243e9afa8
[   34.075353]  ffffc90000527c08 ffffffffa03874c7 ffffc90000527bb8 ffff880243e9afa8
[   34.075383]  ffff880243e9afb0 ffffc90000527e10 ffff8802447fc2a8 ffff880243cb8040
[   34.075414] Call Trace:
[   34.075435]  [<ffffffffa03874c7>] eb_lookup_vmas.isra.7+0x247/0x330 [i915]
[   34.075468]  [<ffffffffa0388c34>] i915_gem_do_execbuffer.isra.15+0x604/0x1a10 [i915]
[   34.075507]  [<ffffffffa039c957>] ? i915_gem_object_get_sg+0x347/0x380 [i915]
[   34.075532]  [<ffffffff811a69ce>] ? __might_fault+0x3e/0x90
[   34.075562]  [<ffffffffa038a430>] i915_gem_execbuffer2+0xc0/0x250 [i915]
[   34.075585]  [<ffffffff81552926>] drm_ioctl+0x1f6/0x480
[   34.075604]  [<ffffffff8100107a>] ? trace_hardirqs_on_thunk+0x1a/0x1c
[   34.075635]  [<ffffffffa038a370>] ? i915_gem_execbuffer+0x330/0x330 [i915]
[   34.075658]  [<ffffffff81202d2e>] do_vfs_ioctl+0x8e/0x690
[   34.075677]  [<ffffffff8181582d>] ? _raw_spin_unlock_irqrestore+0x3d/0x60
[   34.075700]  [<ffffffff810fcd51>] ? SyS_timer_settime+0x141/0x1e0
[   34.075721]  [<ffffffff810d6de2>] ? trace_hardirqs_on_caller+0x122/0x1b0
[   34.075742]  [<ffffffff8120336c>] SyS_ioctl+0x3c/0x70
[   34.075760]  [<ffffffff8181602e>] entry_SYSCALL_64_fastpath+0x1c/0xb1
[   34.075781] Code: 44 a0 48 c7 c2 9a 7e 43 a0 be e0 0d 00 00 48 c7 c7 a0 45 44 a0 e8 55 b8 ce e0 48 85 db 74 a3 49 83 bd f8 03 00 00 00 74 99 0f 0b <0f> 0b 48 89 da 4c 89 ee 4c 89 e7 e8 04 a9 ff ff 48 89 da 49 89
[   34.075955] RIP  [<ffffffffa0392cbc>] i915_gem_obj_lookup_or_create_vma+0x8c/0xc0 [i915]
[   34.075994]  RSP <ffffc90000527b68>

Testcase: igt/gem_close_race/basic-threads
Fixes: db6c2b4151f2 ("drm/i915: Store the vma in an rbtree...")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161104161241.25871-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
johalun pushed a commit that referenced this issue May 1, 2017
In order to walk the list of all timelines, we currently require the
struct_mutex. We are sometimes called prior to the struct_mutex being
taken by the caller (i.e !I915_WAIT_LOCKED) in which case we can only
trust the global execution timelines (as these are owned by the device).
This means in the unlocked phase we can only wait upon the currently
executing requests and not all queued.

[  175.743243] general protection fault: 0000 [#1] SMP
[  175.743263] Modules linked in: nls_iso8859_1 intel_rapl x86_pkg_temp_thermal coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel iwlwifi aesni_intel aes_x86_64 lrw snd_soc_rt5640 gf128mul snd_soc_rl6231 snd_soc_core glue_helper snd_compress snd_pcm_dmaengine snd_hda_codec_hdmi ablk_helper snd_hda_codec_realtek cryptd snd_hda_codec_generic serio_raw cfg80211 snd_hda_intel snd_hda_codec ir_lirc_codec snd_hda_core lirc_dev snd_hwdep snd_pcm lpc_ich mei_me mei snd_seq_midi shpchp snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device snd_timer rc_rc6_mce acpi_als nuvoton_cir kfifo_buf rc_core snd industrialio snd_soc_sst_acpi soundcore snd_soc_sst_match i2c_designware_platform 8250_dw i2c_designware_core dw_dmac spi_pxa2xx_platform mac_hid acpi_pad parport_pc ppdev lp parport
[  175.743509]  autofs4 i915 e1000e psmouse ptp pps_core xhci_pci ehci_pci ahci xhci_hcd ehci_hcd libahci video sdhci_acpi sdhci i2c_hid hid
[  175.743560] CPU: 2 PID: 2386 Comm: wtdg_monitor.sh Tainted: G     U          4.9.0-rc4-nightly+ #2
[  175.743581] Hardware name:                  /NUC5i7RYB, BIOS RYBDWi35.86A.0358.2016.0606.1423 06/06/2016
[  175.743603] task: ffff88024509ba80 task.stack: ffffc9007bd18000
[  175.743618] RIP: 0010:[<ffffffffa01af29b>]  [<ffffffffa01af29b>] i915_gem_wait_for_idle+0x3b/0x140 [i915]
[  175.743660] RSP: 0000:ffffc9007bd1b9b8  EFLAGS: 00010297
[  175.743674] RAX: ffff88024489d248 RBX: 0000000000000000 RCX: 0000000000000000
[  175.743691] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880244898000
[  175.743708] RBP: ffffc9007bd1b9f0 R08: 0000000000000000 R09: 0000000000000001
[  175.743724] R10: 00000028eaf42792 R11: 0000000000000001 R12: dead000000000100
[  175.743741] R13: dead000000000148 R14: ffffc9007bd1ba5f R15: 0000000000000005
[  175.743758] FS:  00007f2638330700(0000) GS:ffff880256d00000(0000) knlGS:0000000000000000
[  175.743777] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  175.743791] CR2: 00007f885c8cea40 CR3: 00000002416b5000 CR4: 00000000003406e0
[  175.743808] Stack:
[  175.743816]  ffff88024489d248 000000004509ba80 ffff880244898000 ffff88024509ba80
[  175.743840]  00000000ffff8b69 ffffc9007bd1ba5f ffffc9007bd1ba5e ffffc9007bd1ba28
[  175.743863]  ffffffffa01b661d 00000000ffffffff 0000000000000000 ffff880244898000
[  175.743886] Call Trace:
[  175.743906]  [<ffffffffa01b661d>] i915_gem_shrinker_lock_uninterruptible.constprop.5+0x5d/0xc0 [i915]
[  175.743937]  [<ffffffffa01b6cd0>] i915_gem_shrinker_oom+0x30/0x1b0 [i915]
[  175.743955]  [<ffffffff8109ca79>] notifier_call_chain+0x49/0x70
[  175.743971]  [<ffffffff8109cd9d>] __blocking_notifier_call_chain+0x4d/0x70
[  175.743988]  [<ffffffff8109cdd6>] blocking_notifier_call_chain+0x16/0x20
[  175.744005]  [<ffffffff811885dc>] out_of_memory+0x22c/0x480
[  175.744020]  [<ffffffff81205542>] __alloc_pages_slowpath+0x851/0x8ec
[  175.744037]  [<ffffffff8118ca51>] __alloc_pages_nodemask+0x2c1/0x310
[  175.744054]  [<ffffffff811d8ea8>] alloc_pages_current+0x88/0x120
[  175.744070]  [<ffffffff811833a4>] __page_cache_alloc+0xb4/0xc0
[  175.744086]  [<ffffffff811865ca>] filemap_fault+0x29a/0x500
[  175.744101]  [<ffffffff81299aa6>] ext4_filemap_fault+0x36/0x50
[  175.744117]  [<ffffffff811b3d4a>] __do_fault+0x6a/0xe0
[  175.744131]  [<ffffffff811b97ee>] handle_mm_fault+0xd0e/0x1330
[  175.744147]  [<ffffffff8106738c>] __do_page_fault+0x23c/0x4d0
[  175.744162]  [<ffffffff81067650>] do_page_fault+0x30/0x80
[  175.744177]  [<ffffffff817ffbe8>] page_fault+0x28/0x30
[  175.744191] Code: 41 57 41 56 41 55 41 54 53 48 83 ec 10 4c 8b a7 48 52 00 00 89 75 d4 48 89 45 c8 49 39 c4 74 78 4d 8d 6c 24 48 41 bf 05 00 00 00 <49> 8b 5d 00 48 85 db 74 50 8b 83 20 01 00 00 85 c0 74 15 48 8b
[  175.744320] RIP  [<ffffffffa01af29b>] i915_gem_wait_for_idle+0x3b/0x140 [i915]
[  175.744351]  RSP <ffffc9007bd1b9b8>

Fixes: 80b204bce8f2 ("drm/i915: Enable multiple timelines")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161111145809.9701-1-chris@chris-wilson.co.uk
markjdb pushed a commit to markjdb/freebsd-base-graphics that referenced this issue May 27, 2017
In the absense of a more specific handler for TRAP_CAP (generated by
ENOTCAPABLE or ECAPMODE while in capability mode) treat it as a trace
trap.

Example usage (testing the bug in PR219173):

% proccontrol -m trapcap lldb usr.bin/hexdump/obj/hexdump -- -Cv -s 1 /bin/ls
...
(lldb) run
Process 12980 launching
Process 12980 launched: '.../usr.bin/hexdump/obj/hexdump' (x86_64)
Process 12980 stopped
* thread FreeBSDDesktop#1, stop reason = trace
    frame #0: 0x0000004b80c65f1a libc.so.7`__sys_lseek + 10
...

In the future we should have LLDB control the trapcap procctl itself
(as it does with ASLR), as well as report a specific stop reason.
This change eliminates an assertion failure from LLDB for now.
johalun pushed a commit that referenced this issue May 29, 2017
Trying to chase an impossible bug (ivb):

[  207.765411] [drm:i915_reset_and_wakeup [i915]] resetting chip
[  207.765734] [drm:i915_gem_reset [i915]] resetting render ring to restart from tail of request 0x4ee834
[  207.765791] [drm:intel_print_rc6_info [i915]] Enabling RC6 states: RC6 on RC6p on RC6pp off
[  207.767213] [drm:intel_guc_setup [i915]] GuC fw status: path (null), fetch NONE, load NONE
[  207.767515] kernel BUG at drivers/gpu/drm/i915/i915_gem_request.c:203!
[  207.767551] invalid opcode: 0000 [#1] PREEMPT SMP
[  207.767576] Modules linked in: snd_hda_intel i915 cdc_ncm usbnet mii x86_pkg_temp_thermal coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core mei_me mei snd_pcm sdhci_pci sdhci mmc_core e1000e ptp pps_core [last unloaded: i915]
[  207.767808] CPU: 3 PID: 8855 Comm: gem_ringfill Tainted: G     U          4.9.0-rc5-CI-Patchwork_3052+ #1
[  207.767854] Hardware name: LENOVO 2356GCG/2356GCG, BIOS G7ET31WW (1.13 ) 07/02/2012
[  207.767894] task: ffff88012c82a740 task.stack: ffffc9000383c000
[  207.767927] RIP: 0010:[<ffffffffa00a0a3a>]  [<ffffffffa00a0a3a>] i915_gem_request_retire+0x2a/0x4b0 [i915]
[  207.767999] RSP: 0018:ffffc9000383fb20  EFLAGS: 00010293
[  207.768027] RAX: 00000000004ee83c RBX: ffff880135dcb480 RCX: 00000000004ee83a
[  207.768062] RDX: ffff88012fea42a8 RSI: 0000000000000001 RDI: ffff88012c82af68
[  207.768095] RBP: ffffc9000383fb48 R08: 0000000000000000 R09: 0000000000000000
[  207.768129] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880135dcb480
[  207.768163] R13: ffff88012fea42a8 R14: 0000000000000000 R15: 00000000000001d8
[  207.768200] FS:  00007f955f658740(0000) GS:ffff88013e2c0000(0000) knlGS:0000000000000000
[  207.768239] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  207.768258] CR2: 0000555899725930 CR3: 00000001316f6000 CR4: 00000000001406e0
[  207.768286] Stack:
[  207.768299]  ffff880135dcb480 ffff880135dcbe00 ffff88012fea42a8 0000000000000000
[  207.768350]  00000000000001d8 ffffc9000383fb70 ffffffffa00a1339 0000000000000000
[  207.768402]  ffff88012f296c88 00000000000003f0 ffffc9000383fbb0 ffffffffa00b582d
[  207.768453] Call Trace:
[  207.768493]  [<ffffffffa00a1339>] i915_gem_request_retire_upto+0x49/0x90 [i915]
[  207.768553]  [<ffffffffa00b582d>] intel_ring_begin+0x15d/0x2d0 [i915]
[  207.768608]  [<ffffffffa00b59cb>] intel_ring_alloc_request_extras+0x2b/0x40 [i915]
[  207.768667]  [<ffffffffa00a2fd9>] i915_gem_request_alloc+0x359/0x440 [i915]
[  207.768723]  [<ffffffffa008bd03>] i915_gem_do_execbuffer.isra.15+0x783/0x1a10 [i915]
[  207.768766]  [<ffffffff811a6a2e>] ? __might_fault+0x3e/0x90
[  207.768816]  [<ffffffffa008d380>] i915_gem_execbuffer2+0xc0/0x250 [i915]
[  207.768854]  [<ffffffff815532a6>] drm_ioctl+0x1f6/0x480
[  207.768900]  [<ffffffffa008d2c0>] ? i915_gem_execbuffer+0x330/0x330 [i915]
[  207.768939]  [<ffffffff81202f6e>] do_vfs_ioctl+0x8e/0x690
[  207.768972]  [<ffffffff818193ac>] ? retint_kernel+0x2d/0x2d
[  207.769004]  [<ffffffff810d6ef2>] ? trace_hardirqs_on_caller+0x122/0x1b0
[  207.769039]  [<ffffffff812035ac>] SyS_ioctl+0x3c/0x70
[  207.769068]  [<ffffffff818189ae>] entry_SYSCALL_64_fastpath+0x1c/0xb1
[  207.769103] Code: 90 55 48 89 e5 41 57 41 56 41 55 41 54 49 89 fc 53 8b 35 fa 7b e1 e1 85 f6 0f 85 55 03 00 00 41 8b 84 24 80 02 00 00 85 c0 75 02 <0f> 0b 49 8b 94 24 a8 00 00 00 48 8b 8a e0 01 00 00 8b 89 c0 00
[  207.769400] RIP  [<ffffffffa00a0a3a>] i915_gem_request_retire+0x2a/0x4b0 [i915]
[  207.769463]  RSP <ffffc9000383fb20>

Let's add a couple more BUG_ONs before this to ascertain that the request
did make it to hardware. The impossible part of this stacktrace is that
request must have been considered completed by the i915_request_wait()
before we tried to retire it.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161118143412.26508-1-chris@chris-wilson.co.uk
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
johalun pushed a commit that referenced this issue May 29, 2017
commit 202b52b7fbf7 ("drm: Track drm_mm nodes with an interval tree")
introduced a requirement that the special drm_mm.head_node was
initialised and marked as not being allocated. It is a very special node
that has no side but has a hole that represents the drm_mm address
space, and holds the list of nodes. Since it is not a real node, it is
not part of the node rbtree and we detect this as it being unallocated.
This presumed that drm_mm_init() was initialising it to zero. It happens
that i915 kzallocs its objects and so it was accidentally setting it,
but for generic use we cannot make that assumption.

[   22.981519] general protection fault: 0000 [#1] SMP
[   22.981521] Modules linked in: test_drm_mm(+) ctr ccm arc4 rt2800usb rt2x00usb rt2800lib rt2x00lib crc_ccitt mac80211 cmac rfcomm bnep snd_hda_codec_realtek snd_hda_codec_hdmi snd_hda_codec_generic snd_hda_intel dcdbas snd_hda_codec x86_pkg_temp_thermal intel_powerclamp btusb snd_hda_core coretemp crct10dif_pclmul cfg80211 btrtl btbcm btintel bluetooth crc32_pclmul ghash_clmulni_intel aesni_intel snd_pcm i2c_hid aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd snd_timer hid_multitouch snd joydev serio_raw lpc_ich mfd_core i2c_designware_platform i2c_designware_core 8250_dw binfmt_misc soundcore acpi_pad nls_iso8859_1 usbhid hid psmouse ahci libahci [last unloaded: test_drm_mm]
[   22.981544] CPU: 1 PID: 2088 Comm: drm_mm Tainted: G        W       4.9.0-rc7+ #234
[   22.981545] Hardware name: Dell Inc. XPS 13 9343/0310JH, BIOS A07 11/11/2015
[   22.981546] task: ffff88020c971cc0 task.stack: ffffc90001728000
[   22.981547] RIP: 0010:[<ffffffff814050f0>]  [<ffffffff814050f0>] drm_mm_interval_tree_add_node+0xa0/0xd0
[   22.981551] RSP: 0018:ffffc9000172ba98  EFLAGS: 00010202
[   22.981552] RAX: 0f0000c69cf63d80 RBX: ffff88020be00000 RCX: ffff88020be00000
[   22.981553] RDX: 0000000000000fff RSI: ffffc9000172bc48 RDI: ffffffff810ac4df
[   22.981553] RBP: ffffc9000172bb08 R08: ffffc9000172bc70 R09: 0000000000000fff
[   22.981554] R10: ffffffff810ac4d7 R11: 4dc04d8b4cffffe5 R12: 0000000000001000
[   22.981555] R13: ffffc9000172bbd0 R14: ffffc9000172bbe0 R15: 0000000002000000
[   22.981556] FS:  00007f80c9fab740(0000) GS:ffff88021f480000(0000) knlGS:0000000000000000
[   22.981557] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   22.981558] CR2: 00007f80c9fd5000 CR3: 000000020c191000 CR4: 00000000003406e0
[   22.981559] Stack:
[   22.981560]  ffffffff81405d09 ffff88020be00000 ffffc9000172bbe0 000000000172bb08
[   22.981562]  ffffffffffffffff 0000000000000000 0000000000000000 0000000000000000
[   22.981563]  0000000002000000 0000000002000000 ffffffffa02f3000 ffff88020be00000
[   22.981565] Call Trace:
[   22.981568]  [<ffffffff81405d09>] ? drm_mm_insert_node_generic+0x229/0x310
[   22.981570]  [<ffffffffa02f3000>] ? 0xffffffffa02f3000
[   22.981572]  [<ffffffffa02903c1>] __subtest_insert_range.constprop.7+0xd1/0x5b0 [test_drm_mm]
[   22.981575]  [<ffffffff81081222>] ? default_wake_function+0x12/0x20
[   22.981576]  [<ffffffff81096905>] ? __wake_up_common+0x55/0x90
[   22.981578]  [<ffffffff81085f42>] ? sched_clock_cpu+0x72/0xa0
[   22.981581]  [<ffffffff811308ad>] ? irq_work_queue+0xd/0x80
[   22.981582]  [<ffffffff810abcc4>] ? wake_up_klogd+0x34/0x40
[   22.981584]  [<ffffffff810ac19d>] ? console_unlock+0x4cd/0x530
[   22.981585]  [<ffffffff810ac4d7>] ? vprintk_emit+0x2d7/0x490
[   22.981587]  [<ffffffff810ac82f>] ? vprintk_default+0x1f/0x30
[   22.981589]  [<ffffffff81146e1c>] ? printk+0x4d/0x4f
[   22.981590]  [<ffffffffa02f3000>] ? 0xffffffffa02f3000
[   22.981592]  [<ffffffffa02908b5>] subtest_insert_range+0x15/0x80 [test_drm_mm]
[   22.981594]  [<ffffffffa02f3088>] test_drm_mm_init+0x88/0x1000 [test_drm_mm]
[   22.981597]  [<ffffffff8100043d>] do_one_initcall+0x3d/0x150
[   22.981600]  [<ffffffff8119dfbf>] ? kfree+0x13f/0x180
[   22.981602]  [<ffffffff811471f2>] do_init_module+0x60/0x1f1
[   22.981606]  [<ffffffff810db878>] load_module+0x2228/0x2790
[   22.981608]  [<ffffffff810d8590>] ? __symbol_put+0x40/0x40
[   22.981612]  [<ffffffff811c52b1>] ? kernel_read+0x41/0x60
[   22.981614]  [<ffffffff810dbfb6>] SYSC_finit_module+0x96/0xd0
[   22.981617]  [<ffffffff810dc00e>] SyS_finit_module+0xe/0x10
[   22.981620]  [<ffffffff816e7aa4>] entry_SYSCALL_64_fastpath+0x17/0x98
[   22.981622] Code: c7 41 30 00 00 00 00 48 89 e5 48 89 3a 48 c7 c2 20 4e 40 81 e8 b2 a1 f0 ff 5d c3 48 8d 56 78 45 31 d2 48 89 d6 eb 25 48 8b 51 58 <48> 39 50 38 73 04 48 89 50 38 4c 8b 58 28 4c 39 59 48 48 8d 50
[   22.981651] RIP  [<ffffffff814050f0>] drm_mm_interval_tree_add_node+0xa0/0xd0
[   22.981655]  RSP <ffffc9000172ba98>

Testcase: igt/drm_mm
Fixes: 202b52b7fbf7 ("drm: Track drm_mm nodes with an interval tree")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.9-rc1+
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161130205126.31106-1-chris@chris-wilson.co.uk
johalun pushed a commit that referenced this issue May 29, 2017
David found another issue with priority bumping from mmioflips, where we
are accessing the requests concurrently to them being retired and freed.
Whilst we are skipping the dependency if has been submitted, that is not
sufficient to stop the dependency from disappearing if another thread
retires that request. To prevent we can either employ the struct_mutex (or a
request mutex in the future) to serialise retiring before it is freed.
Alternatively, we need to keep the dependencies alive using RCU whilst
they are being accessed via the DFS.

[ 1746.698111] general protection fault: 0000 [#1] PREEMPT SMP
[ 1746.698305] Modules linked in: snd_hda_intel snd_hda_codec snd_hwdep x86_pkg_temp_thermal snd_hda_core coretemp crct10dif_pclmul crc32_pclmul snd_pcm ghash_clmulni_intel mei_me mei i915 e1000e ptp pps_core i2c_hid
[ 1746.698750] CPU: 1 PID: 6716 Comm: kworker/u8:2 Not tainted 4.9.0-rc6-CI-Nightly_816+ #1
[ 1746.698871] Hardware name: GIGABYTE GB-BKi7A-7500/MFLP7AP-00, BIOS F1 07/27/2016
[ 1746.699125] Workqueue: events_unbound intel_mmio_flip_work_func [i915]
[ 1746.699266] task: ffff880260a5e800 task.stack: ffffc90000f6c000
[ 1746.699361] RIP: 0010:[<ffffffffa006595d>]  [<ffffffffa006595d>] execlists_schedule+0x8d/0x300 [i915]
[ 1746.699632] RSP: 0018:ffffc90000f6fcd8  EFLAGS: 00010206
[ 1746.699724] RAX: dead0000000000f8 RBX: ffff8801f64b2bf0 RCX: ffff8801f64b2c10
[ 1746.699842] RDX: dead000000000100 RSI: 0000000000000000 RDI: ffff8801f64b0458
[ 1746.699972] RBP: ffffc90000f6fd68 R08: ffff88026488dc00 R09: 0000000000000002
[ 1746.700090] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000400
[ 1746.700195] R13: ffffc90000f6fcf0 R14: ffff88020955aa40 R15: ffff88020955aa68
[ 1746.700307] FS:  0000000000000000(0000) GS:ffff88026dc80000(0000) knlGS:0000000000000000
[ 1746.700435] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1746.700532] CR2: 0000000002a69e90 CR3: 0000000002c07000 CR4: 00000000003406e0
[ 1746.700635] Stack:
[ 1746.700682]  ffff880260a5e880 ffffc90000f6fd50 ffffffff810af69a ffffc90000f6fd28
[ 1746.700827]  ffff88020955a628 ffff8801e1eaebf0 0000000000000020 0000000000000000
[ 1746.700947]  00000196af1edc96 ffff88025dfa4000 ffff8801f0b030a8 ffffc90000f6fcf0
[ 1746.701071] Call Trace:
[ 1746.701117]  [<ffffffff810af69a>] ? dequeue_entity+0x25a/0xb50
[ 1746.701260]  [<ffffffffa00516be>] fence_set_priority+0x7e/0x80 [i915]
[ 1746.701406]  [<ffffffffa0051a15>] i915_gem_object_wait_priority+0x85/0x160 [i915]
[ 1746.701599]  [<ffffffffa008ccd7>] intel_mmio_flip_work_func+0x47/0x2b0 [i915]
[ 1746.701717]  [<ffffffff81094c4d>] process_one_work+0x14d/0x470
[ 1746.701809]  [<ffffffff81094fb3>] worker_thread+0x43/0x4e0
[ 1746.701888]  [<ffffffff81094f70>] ? process_one_work+0x470/0x470
[ 1746.701969]  [<ffffffff81094f70>] ? process_one_work+0x470/0x470
[ 1746.702072]  [<ffffffff8109a4d5>] kthread+0xc5/0xe0
[ 1746.702152]  [<ffffffff81771c59>] ? _raw_spin_unlock_irq+0x9/0x10
[ 1746.702234]  [<ffffffff8109a410>] ? kthread_park+0x60/0x60
[ 1746.702318]  [<ffffffff81772272>] ret_from_fork+0x22/0x30
[ 1746.702387] Code: 89 42 08 48 8b 45 88 48 89 55 c0 4c 89 6d c8 4c 8d 70 d8 4d 8d 7e 28 4d 39 ef 74 72 49 8b 1e 48 8b 13 48 39 d3 48 8d 42 f8 74 3e <48> 8b 10 8b 52 38 41 39 d4 7e 26 48 8b 50 30 48 8b 78 28 48 8d
[ 1746.702921] RIP  [<ffffffffa006595d>] execlists_schedule+0x8d/0x300 [i915]
Nov 25 21:42:54 kbl-gbbki7 kernel: [ 1746.703027]  RSP <ffffc90000f6fcd8>

Fixes: 27745e829a5c ("drm/i915/execlists: Use a local lock for dfs_link access")
Fixes: 9a151987d709 ("drm/i915: Add execution priority boosting for mmioflips")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Weinehall <david.weinehall@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161128143649.4289-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
(cherry picked from commit 92117f0bce64268b841261774e45462cc7ff80af)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
In the error path, we have to be ready to handle an error before either
the state or restore_state have been allocated.

[  397.001342] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  397.001419] IP: [<ffffffffa04347b4>] intel_get_load_detect_pipe+0xe4/0x610 [i915]
[  397.001502] PGD 136a2a067
[  397.001523] PUD 134b5f067
[  397.001546] PMD 0

[  397.001569] Oops: 0002 [#1] PREEMPT SMP
[  397.001599] Modules linked in: snd_hda_intel i915 cdc_ncm usbnet mii x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core snd_pcm lpc_ich mei_me mei sdhci_pci sdhci mmc_core e1000e ptp pps_core [last unloaded: i915]
[  397.001902] CPU: 1 PID: 9287 Comm: kms_force_conne Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1730+ #1
[  397.001965] Hardware name: LENOVO 2356GCG/2356GCG, BIOS G7ET31WW (1.13 ) 07/02/2012
[  397.002017] task: ffff880138c38040 task.stack: ffffc900083e4000
[  397.002057] RIP: 0010:[<ffffffffa04347b4>]  [<ffffffffa04347b4>] intel_get_load_detect_pipe+0xe4/0x610 [i915]
[  397.002153] RSP: 0018:ffffc900083e7ae8  EFLAGS: 00010286
[  397.002191] RAX: 00000000ffffffdd RBX: ffffc900083e7bc8 RCX: 0000000000000006
[  397.002239] RDX: 0000000000000006 RSI: ffff880138c388b8 RDI: ffffc900083e79e0
[  397.002287] RBP: ffffc900083e7b78 R08: 0000000000000000 R09: 0000000000000000
[  397.002335] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[  397.002386] R13: ffff8801305e1158 R14: 00000000ffffffdd R15: 0000000000000000
[  397.002434] FS:  00007fea1b03c740(0000) GS:ffff88013e240000(0000) knlGS:0000000000000000
[  397.002488] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  397.002528] CR2: 0000000000000000 CR3: 00000001361da000 CR4: 00000000001406e0
[  397.002576] Stack:
[  397.002592]  ffff88013046f180 0000000000000000 ffffc900083e7bc0 0000000000000000
[  397.002655]  0000000000000000 ffff8801306bd038 ffff88012e980000 ffffc90000000001
[  397.002718]  ffffc90000000000 ffff880136b8ca88 ffff88012e980890 ffff88012e980540
[  397.002780] Call Trace:
[  397.002828]  [<ffffffffa044e8c4>] intel_crt_detect+0x3c4/0x8f0 [i915]
[  397.002876]  [<ffffffff810e37fa>] ? vprintk_default+0x1a/0x20
[  397.002918]  [<ffffffff8116eb68>] ? printk+0x43/0x4b
[  397.002956]  [<ffffffff81546b06>] drm_helper_probe_single_connector_modes+0x406/0x4f0
[  397.003014]  [<ffffffff81819c09>] ? mutex_unlock+0x9/0x10
[  397.003054]  [<ffffffff815723dc>] drm_mode_getconnector+0x33c/0x3c0
[  397.003099]  [<ffffffff810ed59d>] ? debug_lockdep_rcu_enabled+0x1d/0x20
[  397.003147]  [<ffffffff811a6bae>] ? __might_fault+0x3e/0x90
[  397.003191]  [<ffffffff8155aaf6>] drm_ioctl+0x1f6/0x480
[  397.003231]  [<ffffffff815720a0>] ? drm_mode_connector_property_set_ioctl+0x30/0x30
[  397.003285]  [<ffffffff8120308e>] do_vfs_ioctl+0x8e/0x690
[  397.003324]  [<ffffffff810a102c>] ? task_work_run+0x8c/0xb0
[  397.003366]  [<ffffffff810d6d92>] ? trace_hardirqs_on_caller+0x122/0x1b0
[  397.003412]  [<ffffffff812036cc>] SyS_ioctl+0x3c/0x70
[  397.003451]  [<ffffffff8181df2e>] entry_SYSCALL_64_fastpath+0x1c/0xb1
[  397.003496] Code: 85 c0 41 89 c6 75 57 49 8b 85 f0 00 00 00 48 89 de 45 31 ff 48 8d 78 20 e8 1a 89 13 e1 45 31 c9 85 c0 41 89 c6 0f 84 2f 01 00 00 <f0> 41 83 29 01 74 53 f0 41 83 2f 01 74 2d 41 83 fe dd 75 35 48
[  397.003837] RIP  [<ffffffffa04347b4>] intel_get_load_detect_pipe+0xe4/0x610 [i915]
[  397.003921]  RSP <ffffc900083e7ae8>
[  397.003947] CR2: 0000000000000000

Testcase: igt/kms_force_connector_basic/force-load-detect # ivb-3720m
Fixes: 0853695c3ba4 ("drm: Add reference counting to drm_atomic_state"
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161019113743.19847-1-chris@chris-wilson.co.uk
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
The breadcrumbs are about to be used from within IRQ context sections
(e.g. nouveau signals a fence from an interrupt handler causing us to
submit a new request) and/or from bottom-half tasklets (i.e.
intel_lrc_irq_handler), therefore we need to employ the irqsafe spinlock
variants.

For example, deferring the request submission to the
intel_lrc_irq_handler generates this trace:

[   66.388639] =================================
[   66.388650] [ INFO: inconsistent lock state ]
[   66.388663] 4.9.0-rc2+ #56 Not tainted
[   66.388672] ---------------------------------
[   66.388682] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[   66.388695] swapper/1/0 [HC0[0]:SC1[1]:HE0:SE0] takes:
[   66.388706]  (&(&b->lock)->rlock){+.?...} , at: [<ffffffff81401c88>] intel_engine_enable_signaling+0x78/0x150
[   66.388761] {SOFTIRQ-ON-W} state was registered at:
[   66.388772]   [   66.388783] [<ffffffff810bd842>] __lock_acquire+0x682/0x1870
[   66.388795]   [   66.388803] [<ffffffff810bedbc>] lock_acquire+0x6c/0xb0
[   66.388814]   [   66.388824] [<ffffffff8161753a>] _raw_spin_lock+0x2a/0x40
[   66.388835]   [   66.388845] [<ffffffff81401e41>] intel_engine_reset_breadcrumbs+0x21/0xb0
[   66.388857]   [   66.388866] [<ffffffff81403ae7>] gen8_init_common_ring+0x67/0x100
[   66.388878]   [   66.388887] [<ffffffff81403b92>] gen8_init_render_ring+0x12/0x60
[   66.388903]   [   66.388912] [<ffffffff813f8707>] i915_gem_init_hw+0xf7/0x2a0
[   66.388927]   [   66.388936] [<ffffffff813f899b>] i915_gem_init+0xbb/0xf0
[   66.388950]   [   66.388959] [<ffffffff813b4980>] i915_driver_load+0x7e0/0x1330
[   66.388978]   [   66.388988] [<ffffffff813c09d8>] i915_pci_probe+0x28/0x40
[   66.389003]   [   66.389013] [<ffffffff812fa0db>] pci_device_probe+0x8b/0xf0
[   66.389028]   [   66.389037] [<ffffffff8147737e>] driver_probe_device+0x21e/0x430
[   66.389056]   [   66.389065] [<ffffffff8147766e>] __driver_attach+0xde/0xe0
[   66.389080]   [   66.389090] [<ffffffff814751ad>] bus_for_each_dev+0x5d/0x90
[   66.389105]   [   66.389113] [<ffffffff81477799>] driver_attach+0x19/0x20
[   66.389134]   [   66.389144] [<ffffffff81475ced>] bus_add_driver+0x15d/0x260
[   66.389159]   [   66.389168] [<ffffffff81477e3b>] driver_register+0x5b/0xd0
[   66.389183]   [   66.389281] [<ffffffff812fa19b>] __pci_register_driver+0x5b/0x60
[   66.389301]   [   66.389312] [<ffffffff81aed333>] i915_init+0x3e/0x45
[   66.389326]   [   66.389336] [<ffffffff81ac2ffa>] do_one_initcall+0x8b/0x118
[   66.389350]   [   66.389359] [<ffffffff81ac323a>] kernel_init_freeable+0x1b3/0x23b
[   66.389378]   [   66.389387] [<ffffffff8160fc39>] kernel_init+0x9/0x100
[   66.389402]   [   66.389411] [<ffffffff816180e7>] ret_from_fork+0x27/0x40
[   66.389426] irq event stamp: 315865
[   66.389438] hardirqs last  enabled at (315864): [<ffffffff816178f1>] _raw_spin_unlock_irqrestore+0x31/0x50
[   66.389469] hardirqs last disabled at (315865): [<ffffffff816176b3>] _raw_spin_lock_irqsave+0x13/0x50
[   66.389499] softirqs last  enabled at (315818): [<ffffffff8107a04c>] _local_bh_enable+0x1c/0x50
[   66.389530] softirqs last disabled at (315819): [<ffffffff8107a50e>] irq_exit+0xbe/0xd0
[   66.389559]
[   66.389559] other info that might help us debug this:
[   66.389580]  Possible unsafe locking scenario:
[   66.389580]
[   66.389598]        CPU0
[   66.389609]        ----
[   66.389620]   lock(&(&b->lock)->rlock);
[   66.389650]   <Interrupt>
[   66.389661]     lock(&(&b->lock)->rlock);
[   66.389690]
[   66.389690]  *** DEADLOCK ***
[   66.389690]
[   66.389715] 2 locks held by swapper/1/0:
[   66.389728]  #0: (&(&tl->lock)->rlock){..-...}, at: [<ffffffff81403e01>] intel_lrc_irq_handler+0x201/0x3c0
[   66.389785]  #1: (&(&req->lock)->rlock/1){..-...}, at: [<ffffffff813fc0af>] __i915_gem_request_submit+0x8f/0x170
[   66.389854]
[   66.389854] stack backtrace:
[   66.389959] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.9.0-rc2+ #56
[   66.389976] Hardware name:                  /        , BIOS PYBSWCEL.86A.0027.2015.0507.1758 05/07/2015
[   66.389999]  ffff88027fd03c58 ffffffff812beae5 ffff88027696e680 ffffffff822afe20
[   66.390036]  ffff88027fd03ca8 ffffffff810bb420 0000000000000001 0000000000000000
[   66.390070]  0000000000000000 0000000000000006 0000000000000004 ffff88027696ee10
[   66.390104] Call Trace:
[   66.390117]  <IRQ>
[   66.390128]  [<ffffffff812beae5>] dump_stack+0x68/0x93
[   66.390147]  [<ffffffff810bb420>] print_usage_bug+0x1d0/0x1e0
[   66.390164]  [<ffffffff810bb8a0>] mark_lock+0x470/0x4f0
[   66.390181]  [<ffffffff810ba9d0>] ? print_shortest_lock_dependencies+0x1b0/0x1b0
[   66.390203]  [<ffffffff810bd75d>] __lock_acquire+0x59d/0x1870
[   66.390221]  [<ffffffff810bedbc>] lock_acquire+0x6c/0xb0
[   66.390237]  [<ffffffff810bedbc>] ? lock_acquire+0x6c/0xb0
[   66.390255]  [<ffffffff81401c88>] ? intel_engine_enable_signaling+0x78/0x150
[   66.390273]  [<ffffffff8161753a>] _raw_spin_lock+0x2a/0x40
[   66.390291]  [<ffffffff81401c88>] ? intel_engine_enable_signaling+0x78/0x150
[   66.390309]  [<ffffffff81401c88>] intel_engine_enable_signaling+0x78/0x150
[   66.390327]  [<ffffffff813fc170>] __i915_gem_request_submit+0x150/0x170
[   66.390345]  [<ffffffff81403e8b>] intel_lrc_irq_handler+0x28b/0x3c0
[   66.390363]  [<ffffffff81079d97>] tasklet_action+0x57/0xc0
[   66.390380]  [<ffffffff8107a249>] __do_softirq+0x119/0x240
[   66.390396]  [<ffffffff8107a50e>] irq_exit+0xbe/0xd0
[   66.390414]  [<ffffffff8101afd5>] do_IRQ+0x65/0x110
[   66.390431]  [<ffffffff81618806>] common_interrupt+0x86/0x86
[   66.390446]  <EOI>
[   66.390457]  [<ffffffff814ec6d1>] ? cpuidle_enter_state+0x151/0x200
[   66.390480]  [<ffffffff814ec7a2>] cpuidle_enter+0x12/0x20
[   66.390498]  [<ffffffff810b639e>] call_cpuidle+0x1e/0x40
[   66.390516]  [<ffffffff810b65ae>] cpu_startup_entry+0x10e/0x1f0
[   66.390534]  [<ffffffff81036133>] start_secondary+0x103/0x130

(This is split out of the defer global seqno allocation patch due to
realisation that we need a more complete conversion if we want to defer
request submission even further.)

v2: lockdep was warning about mixed SOFTIRQ contexts not HARDIRQ
contexts so we only need to use spin_lock_bh and not disable interrupts.

v3: We need full irq protection as we may be called from a third party
interrupt handler (via fences).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-32-chris@chris-wilson.co.uk
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
As we may allocate from within the obj->mm.lock we may enter the
shrinker for direct reclaim. Operating on the current object is
prevented by checking for obj->mm.pages (which is only set as the last
operation in the allocation path). However, we need to identify the
single recursion of accessing another object's obj->mm.lock as the two
locks have identical class and so appear to be the same to lockdep,
convincing it that a deadlock is possible. Use mutex_lock_nested() to
remove the false positive.

[ 2165.945734] =================================
[ 2165.945749] [ INFO: inconsistent lock state ]
[ 2165.945765] 4.9.0-rc2+ #2 Tainted: G        W
[ 2165.945781] ---------------------------------
[ 2165.945796] inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
[ 2165.945816] kswapd0/62 [HC0[0]:SC0[0]:HE1:SE1] takes: (&obj->mm.lock){+.+.?.}, at: [<ffffffffc0289a1f>] i915_gem_shrink+0x29f/0x500 [i915]
[ 2165.945904] {RECLAIM_FS-ON-W} state was registered at:
[ 2165.945931] [<ffffffffb10bd50f>] mark_held_locks+0x6f/0xa0
[ 2165.945956] [<ffffffffb10bf889>] lockdep_trace_alloc+0x69/0xc0
[ 2165.945982] [<ffffffffb11eea53>] kmem_cache_alloc_trace+0x33/0x2a0
[ 2165.946019] [<ffffffffc028a28a>] i915_gem_object_get_pages_stolen+0x6a/0xd0 [i915]
[ 2165.946060] [<ffffffffc027e1d0>] ____i915_gem_object_get_pages+0x20/0x60 [i915]
[ 2165.946098] [<ffffffffc027e268>] __i915_gem_object_get_pages+0x58/0x70 [i915]
[ 2165.946138] [<ffffffffc028a3dc>] _i915_gem_object_create_stolen+0xec/0x120 [i915]
[ 2165.946177] [<ffffffffc028af73>] i915_gem_object_create_stolen_for_preallocated+0xf3/0x3f0 [i915]
[ 2165.946222] [<ffffffffc02bae43>] intel_alloc_initial_plane_obj.isra.125+0xd3/0x200 [i915]
[ 2165.946266] [<ffffffffc02cb1c1>] intel_modeset_init+0x931/0x1530 [i915]
[ 2165.946301] [<ffffffffc023d584>] i915_driver_load+0xa14/0x14a0 [i915]
[ 2165.946335] [<ffffffffc0248aff>] i915_pci_probe+0x4f/0x70 [i915]
[ 2165.946362] [<ffffffffb13cc452>] local_pci_probe+0x42/0xa0
[ 2165.946386] [<ffffffffb13cd903>] pci_device_probe+0x103/0x150
[ 2165.946411] [<ffffffffb14adeb3>] driver_probe_device+0x223/0x430
[ 2165.946436] [<ffffffffb14ae1a3>] __driver_attach+0xe3/0xf0
[ 2165.946461] [<ffffffffb14ab943>] bus_for_each_dev+0x73/0xc0
[ 2165.946485] [<ffffffffb14ad5ee>] driver_attach+0x1e/0x20
[ 2165.946508] [<ffffffffb14ad003>] bus_add_driver+0x173/0x270
[ 2165.946533] [<ffffffffb14aee70>] driver_register+0x60/0xe0
[ 2165.946557] [<ffffffffb13cbd6d>] __pci_register_driver+0x5d/0x60
[ 2165.946606] [<ffffffffc0378057>] soundcore_open+0x17/0x230 [soundcore]
[ 2165.946636] [<ffffffffb1000450>] do_one_initcall+0x50/0x180
[ 2165.946661] [<ffffffffb117fd2d>] do_init_module+0x5f/0x1f1
[ 2165.946685] [<ffffffffb1108964>] load_module+0x2174/0x2a80
[ 2165.946709] [<ffffffffb11094df>] SYSC_finit_module+0xdf/0x110
[ 2165.946734] [<ffffffffb110952e>] SyS_finit_module+0xe/0x10
[ 2165.946758] [<ffffffffb1742aea>] entry_SYSCALL_64_fastpath+0x18/0xad
[ 2165.946776] irq event stamp: 90871
[ 2165.946788] hardirqs last  enabled at (90871):
[ 2165.946805] [<ffffffffb173e9da>] __mutex_unlock_slowpath+0x11a/0x1c0
[ 2165.946823] hardirqs last disabled at (90870):
[ 2165.946839] [<ffffffffb173e91b>] __mutex_unlock_slowpath+0x5b/0x1c0
[ 2165.946856] softirqs last  enabled at (90858):
[ 2165.946872] [<ffffffffb174581a>] __do_softirq+0x39a/0x4c6
[ 2165.946887] softirqs last disabled at (90671):
[ 2165.946902] [<ffffffffb1066cea>] irq_exit+0xea/0xf0
[ 2165.946916] other info that might help us debug this:
[ 2165.946936]  Possible unsafe locking scenario:
[ 2165.946955]        CPU0
[ 2165.946965]        ----
[ 2165.946975]   lock(&obj->mm.lock);
[ 2165.947000]   <Interrupt>
[ 2165.947010]     lock(&obj->mm.lock);
[ 2165.947035] *** DEADLOCK ***
[ 2165.947054] 2 locks held by kswapd0/62:
[ 2165.947067]  #0: (shrinker_rwsem){++++..}, at: [<ffffffffb119a20e>] shrink_slab.part.40+0x5e/0x5d0
[ 2165.947120]  #1: (&dev->struct_mutex){+.+.+.}, at: [<ffffffffc028954b>] i915_gem_shrinker_lock+0x1b/0x60 [i915]
[ 2165.948909] stack backtrace:
[ 2165.950650] CPU: 2 PID: 62 Comm: kswapd0 Tainted: G        W 4.9.0-rc2+ #2
[ 2165.951587] Hardware name: LENOVO 80MX/Lenovo E31-80, BIOS DCCN34WW(V2.03) 12/01/2015
[ 2165.952484]  ffffc90000b5f8c8 ffffffffb137f645 ffff88016c5a2700 ffffffffb25f20a0
[ 2165.953395]  ffffc90000b5f918 ffffffffb10bcecd 0000000000000000 ffff880100000001
[ 2165.954305]  0000000000000001 000000000000000a ffff88016c5a2fd0 ffff88016c5a2700
[ 2165.955240] Call Trace:
[ 2165.956170]  [<ffffffffb137f645>] dump_stack+0x68/0x93
[ 2165.957071]  [<ffffffffb10bcecd>] print_usage_bug+0x1dd/0x1f0
[ 2165.957979]  [<ffffffffb10bd439>] mark_lock+0x559/0x5c0
[ 2165.958875]  [<ffffffffb10bc3f0>] ?  print_shortest_lock_dependencies+0x1b0/0x1b0
[ 2165.959829]  [<ffffffffb10be04d>] __lock_acquire+0x66d/0x12a0
[ 2165.960729]  [<ffffffffb11ef541>] ? __slab_free+0xa1/0x340
[ 2165.961625]  [<ffffffffb10dba5d>] ?  debug_lockdep_rcu_enabled+0x1d/0x20
[ 2165.962530]  [<ffffffffb10bd50f>] ? mark_held_locks+0x6f/0xa0
[ 2165.963457]  [<ffffffffb10bf0b0>] lock_acquire+0xf0/0x1f0
[ 2165.964368]  [<ffffffffc0289a1f>] ? i915_gem_shrink+0x29f/0x500 [i915]
[ 2165.965269]  [<ffffffffc0289a1f>] ? i915_gem_shrink+0x29f/0x500 [i915]
[ 2165.966150]  [<ffffffffb173d837>] mutex_lock_nested+0x77/0x420
[ 2165.967030]  [<ffffffffc0289a1f>] ? i915_gem_shrink+0x29f/0x500 [i915]
[ 2165.967952]  [<ffffffffc027c7a1>] ?  __i915_gem_object_put_pages.part.58+0x161/0x1b0 [i915]
[ 2165.968835]  [<ffffffffc0289a1f>] i915_gem_shrink+0x29f/0x500 [i915]
[ 2165.969712]  [<ffffffffc0289e40>] i915_gem_shrinker_scan+0x70/0xb0 [i915]
[ 2165.970591]  [<ffffffffb119a3ae>] shrink_slab.part.40+0x1fe/0x5d0
[ 2165.971504]  [<ffffffffb119f19c>] shrink_node+0x22c/0x320
[ 2165.972371]  [<ffffffffb11a05fb>] kswapd+0x38b/0x9b0
[ 2165.973238]  [<ffffffffb11a0270>] ?  mem_cgroup_shrink_node+0x330/0x330
[ 2165.974068]  [<ffffffffb108630f>] kthread+0xff/0x120
[ 2165.974929]  [<ffffffffb1086210>] ? kthread_park+0x60/0x60
[ 2165.975847]  [<ffffffffb1742d57>] ret_from_fork+0x27/0x40

Reported-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: 1233e2db199d ("drm/i915: Move object backing storage manipulation...")
Testcase: igt/gem_ctx_create/maximum-swap
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161031124048.30355-1-chris@chris-wilson.co.uk
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
To flush all call_rcu() tasks (here from i915_gem_free_object()) we need
to call rcu_barrier() (not synchronize_rcu()). If we don't then we may
still have objects being freed as we continue to teardown the driver -
in particular, the recently released rings may race with the memory
manager shutdown resulting in sporadic:

[  142.217186] WARNING: CPU: 7 PID: 6185 at drivers/gpu/drm/drm_mm.c:932 drm_mm_takedown+0x2e/0x40
[  142.217187] Memory manager not clean during takedown.
[  142.217187] Modules linked in: i915(-) x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic mei_me mei snd_hda_codec_hdmi snd_hda_codec snd_hwdep snd_hda_core snd_pcm e1000e ptp pps_core [last unloaded: snd_hda_intel]
[  142.217199] CPU: 7 PID: 6185 Comm: rmmod Not tainted 4.9.0-rc2-CI-Trybot_242+ #1
[  142.217199] Hardware name: LENOVO 10AGS00601/SHARKBAY, BIOS FBKT34AUS 04/24/2013
[  142.217200]  ffffc90002ecfce0 ffffffff8142dd65 ffffc90002ecfd30 0000000000000000
[  142.217202]  ffffc90002ecfd20 ffffffff8107e4e6 000003a40778c2a8 ffff880401355c48
[  142.217204]  ffff88040778c2a8 ffffffffa040f3c0 ffffffffa040f4a0 00005621fbf8b1f0
[  142.217206] Call Trace:
[  142.217209]  [<ffffffff8142dd65>] dump_stack+0x67/0x92
[  142.217211]  [<ffffffff8107e4e6>] __warn+0xc6/0xe0
[  142.217213]  [<ffffffff8107e54a>] warn_slowpath_fmt+0x4a/0x50
[  142.217214]  [<ffffffff81559e3e>] drm_mm_takedown+0x2e/0x40
[  142.217236]  [<ffffffffa035c02a>] i915_gem_cleanup_stolen+0x1a/0x20 [i915]
[  142.217246]  [<ffffffffa034c581>] i915_ggtt_cleanup_hw+0x31/0xb0 [i915]
[  142.217253]  [<ffffffffa0310311>] i915_driver_cleanup_hw+0x31/0x40 [i915]
[  142.217260]  [<ffffffffa0312001>] i915_driver_unload+0x141/0x1a0 [i915]
[  142.217268]  [<ffffffffa031c2c4>] i915_pci_remove+0x14/0x20 [i915]
[  142.217269]  [<ffffffff8147d214>] pci_device_remove+0x34/0xb0
[  142.217271]  [<ffffffff8157b14c>] __device_release_driver+0x9c/0x150
[  142.217272]  [<ffffffff8157bcc6>] driver_detach+0xb6/0xc0
[  142.217273]  [<ffffffff8157abe3>] bus_remove_driver+0x53/0xd0
[  142.217274]  [<ffffffff8157c787>] driver_unregister+0x27/0x50
[  142.217276]  [<ffffffff8147c265>] pci_unregister_driver+0x25/0x70
[  142.217287]  [<ffffffffa03d764c>] i915_exit+0x1a/0x71 [i915]
[  142.217289]  [<ffffffff811136b3>] SyS_delete_module+0x193/0x1e0
[  142.217291]  [<ffffffff818174ae>] entry_SYSCALL_64_fastpath+0x1c/0xb1
[  142.217292] ---[ end trace 6fd164859c154772 ]---
[  142.217505] [drm:show_leaks] *ERROR* node [6b6b6b6b6b6b6b6b + 6b6b6b6b6b6b6b6b]: inserted at
                [<ffffffff81559ff3>] save_stack.isra.1+0x53/0xa0
                [<ffffffff8155a98d>] drm_mm_insert_node_in_range_generic+0x2ad/0x360
                [<ffffffffa035bf23>] i915_gem_stolen_insert_node_in_range+0x93/0xe0 [i915]
                [<ffffffffa035c855>] i915_gem_object_create_stolen+0x75/0xb0 [i915]
                [<ffffffffa036a51a>] intel_engine_create_ring+0x9a/0x140 [i915]
                [<ffffffffa036a921>] intel_init_ring_buffer+0xf1/0x440 [i915]
                [<ffffffffa036be1b>] intel_init_render_ring_buffer+0xab/0x1b0 [i915]
                [<ffffffffa0363d08>] intel_engines_init+0xc8/0x210 [i915]
                [<ffffffffa0355d7c>] i915_gem_init+0xac/0xf0 [i915]
                [<ffffffffa0311454>] i915_driver_load+0x9c4/0x1430 [i915]
                [<ffffffffa031c2f8>] i915_pci_probe+0x28/0x40 [i915]
                [<ffffffff8147d315>] pci_device_probe+0x85/0xf0
                [<ffffffff8157b7ff>] driver_probe_device+0x21f/0x430
                [<ffffffff8157baee>] __driver_attach+0xde/0xe0

In particular note that the node was being poisoned as we inspected the
list, a  clear indication that the object is being freed as we make the
assertion.

v2: Don't loop, just assert that we do all the work required as that
will be better at detecting further errors.

Fixes: fbbd37b36fa5 ("drm/i915: Move object release to a freelist + worker")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161101084843.3961-1-chris@chris-wilson.co.uk
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
If we have a tiled object and an unknown CPU swizzle pattern, we pin the
pages to prevent the object from being swapped out (and us corrupting
the contents as we do not know the access pattern and so cannot convert
it to linear and back to tiled on reuse). This requires us to remember
to drop the extra pinning when freeing the object, or else we trigger
warnings about the pin leak. In commit fbbd37b36fa5 ("drm/i915: Move
object release to a freelist + worker"), the object free path was
deferred to a worker, but the unpinning of the quirk, along with marking
the object as reclaimable, was left on the immediate path (so that if
required we could reclaim the pages under memory pressure as early as
possible). However, this split introduced a bug where the pages were no
longer being unpinned if they were marked as unneeded.

[  231.800401] WARNING: CPU: 1 PID: 90 at drivers/gpu/drm/i915/i915_gem.c:4275 __i915_gem_free_objects+0x326/0x3c0 [i915]
[  231.800403] WARN_ON(i915_gem_object_has_pinned_pages(obj))
[  231.800405] Modules linked in:
[  231.800406]  snd_hda_intel i915 snd_hda_codec_generic mei_me snd_hda_codec coretemp snd_hwdep mei lpc_ich snd_hda_core snd_pcm e1000e ptp pps_core [last unloaded: i915]
[  231.800426] CPU: 1 PID: 90 Comm: kworker/1:4 Tainted: G     U          4.9.0-rc2-CI-CI_DRM_1780+ #1
[  231.800428] Hardware name: LENOVO 7465CTO/7465CTO, BIOS 6DET44WW (2.08 ) 04/22/2009
[  231.800456] Workqueue: events __i915_gem_free_work [i915]
[  231.800459]  ffffc9000034fc80 ffffffff8142dd65 ffffc9000034fcd0 0000000000000000
[  231.800465]  ffffc9000034fcc0 ffffffff8107e4e6 000010b300000001 0000000000001000
[  231.800469]  ffff88011d3db740 ffff880130ef0000 0000000000000000 ffff880130ef5ea0
[  231.800474] Call Trace:
[  231.800479]  [<ffffffff8142dd65>] dump_stack+0x67/0x92
[  231.800484]  [<ffffffff8107e4e6>] __warn+0xc6/0xe0
[  231.800487]  [<ffffffff8107e54a>] warn_slowpath_fmt+0x4a/0x50
[  231.800491]  [<ffffffff811d12ac>] ? kmem_cache_free+0x2dc/0x340
[  231.800520]  [<ffffffffa009ef36>] __i915_gem_free_objects+0x326/0x3c0 [i915]
[  231.800548]  [<ffffffffa009effe>] __i915_gem_free_work+0x2e/0x50 [i915]
[  231.800552]  [<ffffffff8109c27c>] process_one_work+0x1ec/0x6b0
[  231.800555]  [<ffffffff8109c1f6>] ? process_one_work+0x166/0x6b0
[  231.800558]  [<ffffffff8109c789>] worker_thread+0x49/0x490
[  231.800561]  [<ffffffff8109c740>] ? process_one_work+0x6b0/0x6b0
[  231.800563]  [<ffffffff8109c740>] ? process_one_work+0x6b0/0x6b0
[  231.800566]  [<ffffffff810a2aab>] kthread+0xeb/0x110
[  231.800569]  [<ffffffff810a29c0>] ? kthread_park+0x60/0x60
[  231.800573]  [<ffffffff818164a7>] ret_from_fork+0x27/0x40

Moving to a separate flag for tracking the quirked pin is overkill for
the bug (since we only have to interchange the two tests in
i915_gem_free_object) but it does reduce a complicated test on all
objects and provide a sanitycheck for uncommon code paths.

Fixes: fbbd37b36fa5 ("drm/i915: Move object release to a freelist + worker")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161101100317.11129-2-chris@chris-wilson.co.uk
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
Currently, the vma is being unlink from the object lookup on destroy.
However, we are meant to be decoupling it upon close so that the user
cannot access the closed vma whilst it remains active on the GPU.

[   34.074858] kernel BUG at drivers/gpu/drm/i915/i915_gem_gtt.c:3561!
[   34.074875] invalid opcode: 0000 [#1] PREEMPT SMP
[   34.074888] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich mei_me mei snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep snd_hda_core i2c_designware_platform i2c_designware_core snd_pcm e1000e ptp pps_core sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
[   34.075010] CPU: 1 PID: 6224 Comm: gem_close_race Tainted: G     U          4.9.0-rc3-CI-CI_DRM_1800+ #1
[   34.075034] Hardware name:                  /NUC5i7RYB, BIOS RYBDWi35.86A.0355.2016.0224.1501 02/24/2016
[   34.075057] task: ffff8802459a8040 task.stack: ffffc90000524000
[   34.075074] RIP: 0010:[<ffffffffa0392cbc>]  [<ffffffffa0392cbc>] i915_gem_obj_lookup_or_create_vma+0x8c/0xc0 [i915]
[   34.075118] RSP: 0018:ffffc90000527b68  EFLAGS: 00010202
[   34.075135] RAX: ffff8802426c5e40 RBX: 0000000000000000 RCX: ffff8802447fc2a8
[   34.075158] RDX: 0000000000000000 RSI: ffff8802447fc2a8 RDI: ffff880248a4a880
[   34.075181] RBP: ffffc90000527b88 R08: 0000000000000008 R09: 0000000000000000
[   34.075203] R10: 0000000000000001 R11: 0000000000000000 R12: ffff880248a4a880
[   34.075225] R13: ffff8802447fc2a8 R14: ffff880243e9afa8 R15: ffff880248a4a9c8
[   34.075248] FS:  00007f9b43e59740(0000) GS:ffff880256c80000(0000) knlGS:0000000000000000
[   34.075273] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   34.075292] CR2: 00007f9b43419140 CR3: 000000024455d000 CR4: 00000000003406e0
[   34.075314] Stack:
[   34.075323]  0000000000000000 ffffc90000527bd0 ffff880243cb8008 ffff880243e9afa8
[   34.075353]  ffffc90000527c08 ffffffffa03874c7 ffffc90000527bb8 ffff880243e9afa8
[   34.075383]  ffff880243e9afb0 ffffc90000527e10 ffff8802447fc2a8 ffff880243cb8040
[   34.075414] Call Trace:
[   34.075435]  [<ffffffffa03874c7>] eb_lookup_vmas.isra.7+0x247/0x330 [i915]
[   34.075468]  [<ffffffffa0388c34>] i915_gem_do_execbuffer.isra.15+0x604/0x1a10 [i915]
[   34.075507]  [<ffffffffa039c957>] ? i915_gem_object_get_sg+0x347/0x380 [i915]
[   34.075532]  [<ffffffff811a69ce>] ? __might_fault+0x3e/0x90
[   34.075562]  [<ffffffffa038a430>] i915_gem_execbuffer2+0xc0/0x250 [i915]
[   34.075585]  [<ffffffff81552926>] drm_ioctl+0x1f6/0x480
[   34.075604]  [<ffffffff8100107a>] ? trace_hardirqs_on_thunk+0x1a/0x1c
[   34.075635]  [<ffffffffa038a370>] ? i915_gem_execbuffer+0x330/0x330 [i915]
[   34.075658]  [<ffffffff81202d2e>] do_vfs_ioctl+0x8e/0x690
[   34.075677]  [<ffffffff8181582d>] ? _raw_spin_unlock_irqrestore+0x3d/0x60
[   34.075700]  [<ffffffff810fcd51>] ? SyS_timer_settime+0x141/0x1e0
[   34.075721]  [<ffffffff810d6de2>] ? trace_hardirqs_on_caller+0x122/0x1b0
[   34.075742]  [<ffffffff8120336c>] SyS_ioctl+0x3c/0x70
[   34.075760]  [<ffffffff8181602e>] entry_SYSCALL_64_fastpath+0x1c/0xb1
[   34.075781] Code: 44 a0 48 c7 c2 9a 7e 43 a0 be e0 0d 00 00 48 c7 c7 a0 45 44 a0 e8 55 b8 ce e0 48 85 db 74 a3 49 83 bd f8 03 00 00 00 74 99 0f 0b <0f> 0b 48 89 da 4c 89 ee 4c 89 e7 e8 04 a9 ff ff 48 89 da 49 89
[   34.075955] RIP  [<ffffffffa0392cbc>] i915_gem_obj_lookup_or_create_vma+0x8c/0xc0 [i915]
[   34.075994]  RSP <ffffc90000527b68>

Testcase: igt/gem_close_race/basic-threads
Fixes: db6c2b4151f2 ("drm/i915: Store the vma in an rbtree...")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161104161241.25871-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
In order to walk the list of all timelines, we currently require the
struct_mutex. We are sometimes called prior to the struct_mutex being
taken by the caller (i.e !I915_WAIT_LOCKED) in which case we can only
trust the global execution timelines (as these are owned by the device).
This means in the unlocked phase we can only wait upon the currently
executing requests and not all queued.

[  175.743243] general protection fault: 0000 [#1] SMP
[  175.743263] Modules linked in: nls_iso8859_1 intel_rapl x86_pkg_temp_thermal coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel iwlwifi aesni_intel aes_x86_64 lrw snd_soc_rt5640 gf128mul snd_soc_rl6231 snd_soc_core glue_helper snd_compress snd_pcm_dmaengine snd_hda_codec_hdmi ablk_helper snd_hda_codec_realtek cryptd snd_hda_codec_generic serio_raw cfg80211 snd_hda_intel snd_hda_codec ir_lirc_codec snd_hda_core lirc_dev snd_hwdep snd_pcm lpc_ich mei_me mei snd_seq_midi shpchp snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device snd_timer rc_rc6_mce acpi_als nuvoton_cir kfifo_buf rc_core snd industrialio snd_soc_sst_acpi soundcore snd_soc_sst_match i2c_designware_platform 8250_dw i2c_designware_core dw_dmac spi_pxa2xx_platform mac_hid acpi_pad parport_pc ppdev lp parport
[  175.743509]  autofs4 i915 e1000e psmouse ptp pps_core xhci_pci ehci_pci ahci xhci_hcd ehci_hcd libahci video sdhci_acpi sdhci i2c_hid hid
[  175.743560] CPU: 2 PID: 2386 Comm: wtdg_monitor.sh Tainted: G     U          4.9.0-rc4-nightly+ #2
[  175.743581] Hardware name:                  /NUC5i7RYB, BIOS RYBDWi35.86A.0358.2016.0606.1423 06/06/2016
[  175.743603] task: ffff88024509ba80 task.stack: ffffc9007bd18000
[  175.743618] RIP: 0010:[<ffffffffa01af29b>]  [<ffffffffa01af29b>] i915_gem_wait_for_idle+0x3b/0x140 [i915]
[  175.743660] RSP: 0000:ffffc9007bd1b9b8  EFLAGS: 00010297
[  175.743674] RAX: ffff88024489d248 RBX: 0000000000000000 RCX: 0000000000000000
[  175.743691] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880244898000
[  175.743708] RBP: ffffc9007bd1b9f0 R08: 0000000000000000 R09: 0000000000000001
[  175.743724] R10: 00000028eaf42792 R11: 0000000000000001 R12: dead000000000100
[  175.743741] R13: dead000000000148 R14: ffffc9007bd1ba5f R15: 0000000000000005
[  175.743758] FS:  00007f2638330700(0000) GS:ffff880256d00000(0000) knlGS:0000000000000000
[  175.743777] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  175.743791] CR2: 00007f885c8cea40 CR3: 00000002416b5000 CR4: 00000000003406e0
[  175.743808] Stack:
[  175.743816]  ffff88024489d248 000000004509ba80 ffff880244898000 ffff88024509ba80
[  175.743840]  00000000ffff8b69 ffffc9007bd1ba5f ffffc9007bd1ba5e ffffc9007bd1ba28
[  175.743863]  ffffffffa01b661d 00000000ffffffff 0000000000000000 ffff880244898000
[  175.743886] Call Trace:
[  175.743906]  [<ffffffffa01b661d>] i915_gem_shrinker_lock_uninterruptible.constprop.5+0x5d/0xc0 [i915]
[  175.743937]  [<ffffffffa01b6cd0>] i915_gem_shrinker_oom+0x30/0x1b0 [i915]
[  175.743955]  [<ffffffff8109ca79>] notifier_call_chain+0x49/0x70
[  175.743971]  [<ffffffff8109cd9d>] __blocking_notifier_call_chain+0x4d/0x70
[  175.743988]  [<ffffffff8109cdd6>] blocking_notifier_call_chain+0x16/0x20
[  175.744005]  [<ffffffff811885dc>] out_of_memory+0x22c/0x480
[  175.744020]  [<ffffffff81205542>] __alloc_pages_slowpath+0x851/0x8ec
[  175.744037]  [<ffffffff8118ca51>] __alloc_pages_nodemask+0x2c1/0x310
[  175.744054]  [<ffffffff811d8ea8>] alloc_pages_current+0x88/0x120
[  175.744070]  [<ffffffff811833a4>] __page_cache_alloc+0xb4/0xc0
[  175.744086]  [<ffffffff811865ca>] filemap_fault+0x29a/0x500
[  175.744101]  [<ffffffff81299aa6>] ext4_filemap_fault+0x36/0x50
[  175.744117]  [<ffffffff811b3d4a>] __do_fault+0x6a/0xe0
[  175.744131]  [<ffffffff811b97ee>] handle_mm_fault+0xd0e/0x1330
[  175.744147]  [<ffffffff8106738c>] __do_page_fault+0x23c/0x4d0
[  175.744162]  [<ffffffff81067650>] do_page_fault+0x30/0x80
[  175.744177]  [<ffffffff817ffbe8>] page_fault+0x28/0x30
[  175.744191] Code: 41 57 41 56 41 55 41 54 53 48 83 ec 10 4c 8b a7 48 52 00 00 89 75 d4 48 89 45 c8 49 39 c4 74 78 4d 8d 6c 24 48 41 bf 05 00 00 00 <49> 8b 5d 00 48 85 db 74 50 8b 83 20 01 00 00 85 c0 74 15 48 8b
[  175.744320] RIP  [<ffffffffa01af29b>] i915_gem_wait_for_idle+0x3b/0x140 [i915]
[  175.744351]  RSP <ffffc9007bd1b9b8>

Fixes: 80b204bce8f2 ("drm/i915: Enable multiple timelines")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161111145809.9701-1-chris@chris-wilson.co.uk
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
Trying to chase an impossible bug (ivb):

[  207.765411] [drm:i915_reset_and_wakeup [i915]] resetting chip
[  207.765734] [drm:i915_gem_reset [i915]] resetting render ring to restart from tail of request 0x4ee834
[  207.765791] [drm:intel_print_rc6_info [i915]] Enabling RC6 states: RC6 on RC6p on RC6pp off
[  207.767213] [drm:intel_guc_setup [i915]] GuC fw status: path (null), fetch NONE, load NONE
[  207.767515] kernel BUG at drivers/gpu/drm/i915/i915_gem_request.c:203!
[  207.767551] invalid opcode: 0000 [#1] PREEMPT SMP
[  207.767576] Modules linked in: snd_hda_intel i915 cdc_ncm usbnet mii x86_pkg_temp_thermal coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core mei_me mei snd_pcm sdhci_pci sdhci mmc_core e1000e ptp pps_core [last unloaded: i915]
[  207.767808] CPU: 3 PID: 8855 Comm: gem_ringfill Tainted: G     U          4.9.0-rc5-CI-Patchwork_3052+ #1
[  207.767854] Hardware name: LENOVO 2356GCG/2356GCG, BIOS G7ET31WW (1.13 ) 07/02/2012
[  207.767894] task: ffff88012c82a740 task.stack: ffffc9000383c000
[  207.767927] RIP: 0010:[<ffffffffa00a0a3a>]  [<ffffffffa00a0a3a>] i915_gem_request_retire+0x2a/0x4b0 [i915]
[  207.767999] RSP: 0018:ffffc9000383fb20  EFLAGS: 00010293
[  207.768027] RAX: 00000000004ee83c RBX: ffff880135dcb480 RCX: 00000000004ee83a
[  207.768062] RDX: ffff88012fea42a8 RSI: 0000000000000001 RDI: ffff88012c82af68
[  207.768095] RBP: ffffc9000383fb48 R08: 0000000000000000 R09: 0000000000000000
[  207.768129] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880135dcb480
[  207.768163] R13: ffff88012fea42a8 R14: 0000000000000000 R15: 00000000000001d8
[  207.768200] FS:  00007f955f658740(0000) GS:ffff88013e2c0000(0000) knlGS:0000000000000000
[  207.768239] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  207.768258] CR2: 0000555899725930 CR3: 00000001316f6000 CR4: 00000000001406e0
[  207.768286] Stack:
[  207.768299]  ffff880135dcb480 ffff880135dcbe00 ffff88012fea42a8 0000000000000000
[  207.768350]  00000000000001d8 ffffc9000383fb70 ffffffffa00a1339 0000000000000000
[  207.768402]  ffff88012f296c88 00000000000003f0 ffffc9000383fbb0 ffffffffa00b582d
[  207.768453] Call Trace:
[  207.768493]  [<ffffffffa00a1339>] i915_gem_request_retire_upto+0x49/0x90 [i915]
[  207.768553]  [<ffffffffa00b582d>] intel_ring_begin+0x15d/0x2d0 [i915]
[  207.768608]  [<ffffffffa00b59cb>] intel_ring_alloc_request_extras+0x2b/0x40 [i915]
[  207.768667]  [<ffffffffa00a2fd9>] i915_gem_request_alloc+0x359/0x440 [i915]
[  207.768723]  [<ffffffffa008bd03>] i915_gem_do_execbuffer.isra.15+0x783/0x1a10 [i915]
[  207.768766]  [<ffffffff811a6a2e>] ? __might_fault+0x3e/0x90
[  207.768816]  [<ffffffffa008d380>] i915_gem_execbuffer2+0xc0/0x250 [i915]
[  207.768854]  [<ffffffff815532a6>] drm_ioctl+0x1f6/0x480
[  207.768900]  [<ffffffffa008d2c0>] ? i915_gem_execbuffer+0x330/0x330 [i915]
[  207.768939]  [<ffffffff81202f6e>] do_vfs_ioctl+0x8e/0x690
[  207.768972]  [<ffffffff818193ac>] ? retint_kernel+0x2d/0x2d
[  207.769004]  [<ffffffff810d6ef2>] ? trace_hardirqs_on_caller+0x122/0x1b0
[  207.769039]  [<ffffffff812035ac>] SyS_ioctl+0x3c/0x70
[  207.769068]  [<ffffffff818189ae>] entry_SYSCALL_64_fastpath+0x1c/0xb1
[  207.769103] Code: 90 55 48 89 e5 41 57 41 56 41 55 41 54 49 89 fc 53 8b 35 fa 7b e1 e1 85 f6 0f 85 55 03 00 00 41 8b 84 24 80 02 00 00 85 c0 75 02 <0f> 0b 49 8b 94 24 a8 00 00 00 48 8b 8a e0 01 00 00 8b 89 c0 00
[  207.769400] RIP  [<ffffffffa00a0a3a>] i915_gem_request_retire+0x2a/0x4b0 [i915]
[  207.769463]  RSP <ffffc9000383fb20>

Let's add a couple more BUG_ONs before this to ascertain that the request
did make it to hardware. The impossible part of this stacktrace is that
request must have been considered completed by the i915_request_wait()
before we tried to retire it.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161118143412.26508-1-chris@chris-wilson.co.uk
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
David found another issue with priority bumping from mmioflips, where we
are accessing the requests concurrently to them being retired and freed.
Whilst we are skipping the dependency if has been submitted, that is not
sufficient to stop the dependency from disappearing if another thread
retires that request. To prevent we can either employ the struct_mutex (or a
request mutex in the future) to serialise retiring before it is freed.
Alternatively, we need to keep the dependencies alive using RCU whilst
they are being accessed via the DFS.

[ 1746.698111] general protection fault: 0000 [#1] PREEMPT SMP
[ 1746.698305] Modules linked in: snd_hda_intel snd_hda_codec snd_hwdep x86_pkg_temp_thermal snd_hda_core coretemp crct10dif_pclmul crc32_pclmul snd_pcm ghash_clmulni_intel mei_me mei i915 e1000e ptp pps_core i2c_hid
[ 1746.698750] CPU: 1 PID: 6716 Comm: kworker/u8:2 Not tainted 4.9.0-rc6-CI-Nightly_816+ #1
[ 1746.698871] Hardware name: GIGABYTE GB-BKi7A-7500/MFLP7AP-00, BIOS F1 07/27/2016
[ 1746.699125] Workqueue: events_unbound intel_mmio_flip_work_func [i915]
[ 1746.699266] task: ffff880260a5e800 task.stack: ffffc90000f6c000
[ 1746.699361] RIP: 0010:[<ffffffffa006595d>]  [<ffffffffa006595d>] execlists_schedule+0x8d/0x300 [i915]
[ 1746.699632] RSP: 0018:ffffc90000f6fcd8  EFLAGS: 00010206
[ 1746.699724] RAX: dead0000000000f8 RBX: ffff8801f64b2bf0 RCX: ffff8801f64b2c10
[ 1746.699842] RDX: dead000000000100 RSI: 0000000000000000 RDI: ffff8801f64b0458
[ 1746.699972] RBP: ffffc90000f6fd68 R08: ffff88026488dc00 R09: 0000000000000002
[ 1746.700090] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000400
[ 1746.700195] R13: ffffc90000f6fcf0 R14: ffff88020955aa40 R15: ffff88020955aa68
[ 1746.700307] FS:  0000000000000000(0000) GS:ffff88026dc80000(0000) knlGS:0000000000000000
[ 1746.700435] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1746.700532] CR2: 0000000002a69e90 CR3: 0000000002c07000 CR4: 00000000003406e0
[ 1746.700635] Stack:
[ 1746.700682]  ffff880260a5e880 ffffc90000f6fd50 ffffffff810af69a ffffc90000f6fd28
[ 1746.700827]  ffff88020955a628 ffff8801e1eaebf0 0000000000000020 0000000000000000
[ 1746.700947]  00000196af1edc96 ffff88025dfa4000 ffff8801f0b030a8 ffffc90000f6fcf0
[ 1746.701071] Call Trace:
[ 1746.701117]  [<ffffffff810af69a>] ? dequeue_entity+0x25a/0xb50
[ 1746.701260]  [<ffffffffa00516be>] fence_set_priority+0x7e/0x80 [i915]
[ 1746.701406]  [<ffffffffa0051a15>] i915_gem_object_wait_priority+0x85/0x160 [i915]
[ 1746.701599]  [<ffffffffa008ccd7>] intel_mmio_flip_work_func+0x47/0x2b0 [i915]
[ 1746.701717]  [<ffffffff81094c4d>] process_one_work+0x14d/0x470
[ 1746.701809]  [<ffffffff81094fb3>] worker_thread+0x43/0x4e0
[ 1746.701888]  [<ffffffff81094f70>] ? process_one_work+0x470/0x470
[ 1746.701969]  [<ffffffff81094f70>] ? process_one_work+0x470/0x470
[ 1746.702072]  [<ffffffff8109a4d5>] kthread+0xc5/0xe0
[ 1746.702152]  [<ffffffff81771c59>] ? _raw_spin_unlock_irq+0x9/0x10
[ 1746.702234]  [<ffffffff8109a410>] ? kthread_park+0x60/0x60
[ 1746.702318]  [<ffffffff81772272>] ret_from_fork+0x22/0x30
[ 1746.702387] Code: 89 42 08 48 8b 45 88 48 89 55 c0 4c 89 6d c8 4c 8d 70 d8 4d 8d 7e 28 4d 39 ef 74 72 49 8b 1e 48 8b 13 48 39 d3 48 8d 42 f8 74 3e <48> 8b 10 8b 52 38 41 39 d4 7e 26 48 8b 50 30 48 8b 78 28 48 8d
[ 1746.702921] RIP  [<ffffffffa006595d>] execlists_schedule+0x8d/0x300 [i915]
Nov 25 21:42:54 kbl-gbbki7 kernel: [ 1746.703027]  RSP <ffffc90000f6fcd8>

Fixes: 27745e829a5c ("drm/i915/execlists: Use a local lock for dfs_link access")
Fixes: 9a151987d709 ("drm/i915: Add execution priority boosting for mmioflips")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Weinehall <david.weinehall@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161128143649.4289-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
commit 202b52b7fbf7 ("drm: Track drm_mm nodes with an interval tree")
introduced a requirement that the special drm_mm.head_node was
initialised and marked as not being allocated. It is a very special node
that has no side but has a hole that represents the drm_mm address
space, and holds the list of nodes. Since it is not a real node, it is
not part of the node rbtree and we detect this as it being unallocated.
This presumed that drm_mm_init() was initialising it to zero. It happens
that i915 kzallocs its objects and so it was accidentally setting it,
but for generic use we cannot make that assumption.

[   22.981519] general protection fault: 0000 [#1] SMP
[   22.981521] Modules linked in: test_drm_mm(+) ctr ccm arc4 rt2800usb rt2x00usb rt2800lib rt2x00lib crc_ccitt mac80211 cmac rfcomm bnep snd_hda_codec_realtek snd_hda_codec_hdmi snd_hda_codec_generic snd_hda_intel dcdbas snd_hda_codec x86_pkg_temp_thermal intel_powerclamp btusb snd_hda_core coretemp crct10dif_pclmul cfg80211 btrtl btbcm btintel bluetooth crc32_pclmul ghash_clmulni_intel aesni_intel snd_pcm i2c_hid aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd snd_timer hid_multitouch snd joydev serio_raw lpc_ich mfd_core i2c_designware_platform i2c_designware_core 8250_dw binfmt_misc soundcore acpi_pad nls_iso8859_1 usbhid hid psmouse ahci libahci [last unloaded: test_drm_mm]
[   22.981544] CPU: 1 PID: 2088 Comm: drm_mm Tainted: G        W       4.9.0-rc7+ #234
[   22.981545] Hardware name: Dell Inc. XPS 13 9343/0310JH, BIOS A07 11/11/2015
[   22.981546] task: ffff88020c971cc0 task.stack: ffffc90001728000
[   22.981547] RIP: 0010:[<ffffffff814050f0>]  [<ffffffff814050f0>] drm_mm_interval_tree_add_node+0xa0/0xd0
[   22.981551] RSP: 0018:ffffc9000172ba98  EFLAGS: 00010202
[   22.981552] RAX: 0f0000c69cf63d80 RBX: ffff88020be00000 RCX: ffff88020be00000
[   22.981553] RDX: 0000000000000fff RSI: ffffc9000172bc48 RDI: ffffffff810ac4df
[   22.981553] RBP: ffffc9000172bb08 R08: ffffc9000172bc70 R09: 0000000000000fff
[   22.981554] R10: ffffffff810ac4d7 R11: 4dc04d8b4cffffe5 R12: 0000000000001000
[   22.981555] R13: ffffc9000172bbd0 R14: ffffc9000172bbe0 R15: 0000000002000000
[   22.981556] FS:  00007f80c9fab740(0000) GS:ffff88021f480000(0000) knlGS:0000000000000000
[   22.981557] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   22.981558] CR2: 00007f80c9fd5000 CR3: 000000020c191000 CR4: 00000000003406e0
[   22.981559] Stack:
[   22.981560]  ffffffff81405d09 ffff88020be00000 ffffc9000172bbe0 000000000172bb08
[   22.981562]  ffffffffffffffff 0000000000000000 0000000000000000 0000000000000000
[   22.981563]  0000000002000000 0000000002000000 ffffffffa02f3000 ffff88020be00000
[   22.981565] Call Trace:
[   22.981568]  [<ffffffff81405d09>] ? drm_mm_insert_node_generic+0x229/0x310
[   22.981570]  [<ffffffffa02f3000>] ? 0xffffffffa02f3000
[   22.981572]  [<ffffffffa02903c1>] __subtest_insert_range.constprop.7+0xd1/0x5b0 [test_drm_mm]
[   22.981575]  [<ffffffff81081222>] ? default_wake_function+0x12/0x20
[   22.981576]  [<ffffffff81096905>] ? __wake_up_common+0x55/0x90
[   22.981578]  [<ffffffff81085f42>] ? sched_clock_cpu+0x72/0xa0
[   22.981581]  [<ffffffff811308ad>] ? irq_work_queue+0xd/0x80
[   22.981582]  [<ffffffff810abcc4>] ? wake_up_klogd+0x34/0x40
[   22.981584]  [<ffffffff810ac19d>] ? console_unlock+0x4cd/0x530
[   22.981585]  [<ffffffff810ac4d7>] ? vprintk_emit+0x2d7/0x490
[   22.981587]  [<ffffffff810ac82f>] ? vprintk_default+0x1f/0x30
[   22.981589]  [<ffffffff81146e1c>] ? printk+0x4d/0x4f
[   22.981590]  [<ffffffffa02f3000>] ? 0xffffffffa02f3000
[   22.981592]  [<ffffffffa02908b5>] subtest_insert_range+0x15/0x80 [test_drm_mm]
[   22.981594]  [<ffffffffa02f3088>] test_drm_mm_init+0x88/0x1000 [test_drm_mm]
[   22.981597]  [<ffffffff8100043d>] do_one_initcall+0x3d/0x150
[   22.981600]  [<ffffffff8119dfbf>] ? kfree+0x13f/0x180
[   22.981602]  [<ffffffff811471f2>] do_init_module+0x60/0x1f1
[   22.981606]  [<ffffffff810db878>] load_module+0x2228/0x2790
[   22.981608]  [<ffffffff810d8590>] ? __symbol_put+0x40/0x40
[   22.981612]  [<ffffffff811c52b1>] ? kernel_read+0x41/0x60
[   22.981614]  [<ffffffff810dbfb6>] SYSC_finit_module+0x96/0xd0
[   22.981617]  [<ffffffff810dc00e>] SyS_finit_module+0xe/0x10
[   22.981620]  [<ffffffff816e7aa4>] entry_SYSCALL_64_fastpath+0x17/0x98
[   22.981622] Code: c7 41 30 00 00 00 00 48 89 e5 48 89 3a 48 c7 c2 20 4e 40 81 e8 b2 a1 f0 ff 5d c3 48 8d 56 78 45 31 d2 48 89 d6 eb 25 48 8b 51 58 <48> 39 50 38 73 04 48 89 50 38 4c 8b 58 28 4c 39 59 48 48 8d 50
[   22.981651] RIP  [<ffffffff814050f0>] drm_mm_interval_tree_add_node+0xa0/0xd0
[   22.981655]  RSP <ffffc9000172ba98>

Testcase: igt/drm_mm
Fixes: 202b52b7fbf7 ("drm: Track drm_mm nodes with an interval tree")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.9-rc1+
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161130205126.31106-1-chris@chris-wilson.co.uk
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
Since commit 8a357d10043c ("drm: Nerf DRM_CONTROL nodes"), a
struct drm_device's ->control member is always NULL.

In the case of CONFIG_DEBUG_FS=y, radeon_debugfs_add_files() accesses
->control->debugfs_root though. This results in the following Oops:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
  IP: radeon_debugfs_add_files+0x90/0x100 [radeon]
  PGD 0
  Oops: 0000 [#1] SMP
  [...]
  Call Trace:
   ? work_on_cpu+0xb0/0xb0
   radeon_fence_driver_init+0x120/0x150 [radeon]
   si_init+0x122/0xd50 [radeon]
   ? _raw_spin_unlock_irq+0x2c/0x40
   ? device_pm_check_callbacks+0xb3/0xc0
   radeon_device_init+0x958/0xda0 [radeon]
   radeon_driver_load_kms+0x9a/0x210 [radeon]
   drm_dev_register+0xa9/0xd0 [drm]
   drm_get_pci_dev+0x9c/0x1e0 [drm]
   radeon_pci_probe+0xb8/0xe0 [radeon]
  [...]

Fix this by omitting the drm_debugfs_create_files() call for the
control minor debugfs directory which is now non-existent anyway.

Fixes: 8a357d10043c ("drm: Nerf DRM_CONTROL nodes")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161203144700.2307-1-nicstange@gmail.com
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
It is an error to start a new request on the same timeline (ringbuffer)
as the current one before the current is submitted. If there are two
requests emitting to the ringbuffer at the same time, the operation is
undefined. We can catch this by checking for the timeline having a later
seqno than ours when we come to submit our request.

Currently we have this check at the end of __i915_add_request, but
having an early check as well isolates a failure in the caller versus a
failure in sealing the request (i.e. from inside __i915_add_request
itself). For example, CI is currently tripping over this late assertion
on ctg/ilk:

[  100.329399] [IGT] gem_cs_tlb: starting subtest basic-default
[  100.336333] ------------[ cut here ]------------
[  100.336341] kernel BUG at drivers/gpu/drm/i915/i915_gem_request.c:908!
[  100.336347] invalid opcode: 0000 [#1] PREEMPT SMP
[  100.336351] Modules linked in: snd_hda_intel i915 snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core snd_pcm coretemp mei_me lpc_ich mei e1000e ptp pps_core [last unloaded: i915]
[  100.336373] CPU: 0 PID: 6308 Comm: gem_cs_tlb Tainted: G     U          4.10.0-rc3-CI-CI_DRM_2045+ #1
[  100.336380] Hardware name: LENOVO 7465CTO/7465CTO, BIOS 6DET44WW (2.08 ) 04/22/2009
[  100.336386] task: ffff88012b738040 task.stack: ffffc90000560000
[  100.336441] RIP: 0010:__i915_add_request+0x4aa/0x510 [i915]
[  100.336445] RSP: 0018:ffffc90000563ac0 EFLAGS: 00010212
[  100.336451] RAX: 0000000000005d52 RBX: ffff880133bb84c0 RCX: 0000000000000001
[  100.336456] RDX: 0000000080000001 RSI: ffff88012b738860 RDI: 00000000ffffffff
[  100.336461] RBP: ffffc90000563b00 R08: ffff880133bb8780 R09: 0000000000000000
[  100.336466] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88012f53d950
[  100.336472] R13: ffff88012a2b0af8 R14: ffff88012a5b0008 R15: ffff88012f53d960
[  100.336477] FS:  00007f0d19da38c0(0000) GS:ffff88013bc00000(0000) knlGS:0000000000000000
[  100.336483] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  100.336488] CR2: 00007f0d17706000 CR3: 000000012aa3e000 CR4: 00000000000406f0
[  100.336496] Call Trace:
[  100.336527]  i915_gem_switch_to_kernel_context+0x131/0x1b0 [i915]
[  100.336559]  i915_gem_evict_vm+0x202/0x2b0 [i915]
[  100.336590]  i915_gem_execbuffer_reserve.isra.9+0x3ae/0x440 [i915]
[  100.336623]  i915_gem_do_execbuffer.isra.15+0x6d9/0x1b20 [i915]
[  100.336656]  i915_gem_execbuffer2+0xc0/0x250 [i915]
[  100.336666]  drm_ioctl+0x200/0x450
[  100.336697]  ? i915_gem_execbuffer+0x330/0x330 [i915]
[  100.336708]  do_vfs_ioctl+0x90/0x6e0
[  100.336716]  ? up_read+0x1a/0x40
[  100.336723]  ? trace_hardirqs_on_caller+0x122/0x1b0
[  100.336730]  SyS_ioctl+0x3c/0x70
[  100.336738]  entry_SYSCALL_64_fastpath+0x1c/0xb1
[  100.336745] RIP: 0033:0x7f0d187cb357
[  100.336750] RSP: 002b:00007ffe0b2f7c28 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[  100.336761] RAX: ffffffffffffffda RBX: 00007ffe0b2f7d60 RCX: 00007f0d187cb357
[  100.336768] RDX: 00007ffe0b2f7d00 RSI: 0000000040406469 RDI: 0000000000000003
[  100.336775] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000022
[  100.336782] R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000002
[  100.336789] R13: 0000000000419101 R14: 00007ffe0b2f7d60 R15: 00007ffe0b2f7d50
[  100.336797] Code: 5f 74 1e e9 d4 fb ff ff e8 bc 1e 9c e0 e9 ae fb ff ff 4c 89 e7 e8 77 22 fd ff e9 88 fd ff ff 0f 0b e8 a3 1e 9c e0 e9 b1 fb ff ff <0f> 0b 0f 0b e8 fd af ab e0 85 c0 75 c2 48 c7 c2 80 2c 71 a0 be
[  100.336877] RIP: __i915_add_request+0x4aa/0x510 [i915] RSP: ffffc90000563ac0
[  100.336886] ---[ end trace 22b36545479e5eb7 ]---

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170111140858.1922-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
The vma->exec_list is still the only means we have for both reserving an
object in execbuf, and for constructing the eviction list. So during the
construction of the eviction list, we must treat anything already on the
exec_list as being pinned.

Yes, this sharing of two semantically different lists will be fixed! But
in the meantime, we have the issue that this is tripping up CI since we
started using i915_gem_gtt_reserve_node() + i915_gem_evict_for_node()
from the regular execbuf reservation path in commit 606fec956c0e
("drm/i915: Prefer random replacement before eviction search"):

[  108.424063] kernel BUG at drivers/gpu/drm/i915/i915_vma.h:254!
[  108.424072] invalid opcode: 0000 [#1] PREEMPT SMP
[  108.424079] Modules linked in: snd_hda_intel i915 intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_codec_hdmi snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core mei_me snd_pcm lpc_ich mei sdhci_pci sdhci mmc_core e1000e ptp pps_core [last unloaded: i915]
[  108.424132] CPU: 1 PID: 6865 Comm: gem_cs_tlb Tainted: G     U          4.10.0-rc3-CI-CI_DRM_2049+ #1
[  108.424143] Hardware name: Hewlett-Packard HP EliteBook 8440p/172A, BIOS 68CCU Ver. F.24 09/13/2013
[  108.424154] task: ffff88012ae22600 task.stack: ffffc90000a14000
[  108.424220] RIP: 0010:i915_gem_evict_for_node+0x237/0x410 [i915]
[  108.424229] RSP: 0018:ffffc90000a17a58 EFLAGS: 00010202
[  108.424237] RAX: 0000000000005871 RBX: ffff88012d1ad778 RCX: 0000000000000000
[  108.424246] RDX: 000000007ffff000 RSI: ffffc90000a17a68 RDI: ffff880127e694d8
[  108.424255] RBP: ffffc90000a17aa0 R08: ffffc90000a17a68 R09: 0000000000000000
[  108.424264] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000080000000
[  108.424273] R13: ffffc90000a17a68 R14: ffff880127e694d8 R15: ffffffffa0387330
[  108.424283] FS:  00007f8236e3d8c0(0000) GS:ffff880137c40000(0000) knlGS:0000000000000000
[  108.424293] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  108.424305] CR2: 00007f82347a2000 CR3: 000000012c866000 CR4: 00000000000006e0
[  108.424317] Call Trace:
[  108.424368]  i915_gem_gtt_reserve+0x67/0x80 [i915]
[  108.424424]  __i915_vma_do_pin+0x248/0x620 [i915]
[  108.424487]  ? __i915_vma_do_pin+0x162/0x620 [i915]
[  108.424540]  i915_gem_execbuffer_reserve_vma.isra.8+0x153/0x1f0 [i915]
[  108.424591]  i915_gem_execbuffer_reserve.isra.9+0x40e/0x440 [i915]
[  108.424643]  i915_gem_do_execbuffer.isra.15+0x6d9/0x1b20 [i915]
[  108.424696]  i915_gem_execbuffer2+0xc0/0x250 [i915]
[  108.424712]  drm_ioctl+0x200/0x450
[  108.424760]  ? i915_gem_execbuffer+0x330/0x330 [i915]
[  108.424776]  do_vfs_ioctl+0x90/0x6e0
[  108.424789]  ? up_read+0x1a/0x40
[  108.424800]  ? trace_hardirqs_on_caller+0x122/0x1b0
[  108.424813]  SyS_ioctl+0x3c/0x70
[  108.424828]  entry_SYSCALL_64_fastpath+0x1c/0xb1
[  108.424839] RIP: 0033:0x7f8235867357
[  108.424848] RSP: 002b:00007ffdc14504c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[  108.424866] RAX: ffffffffffffffda RBX: 00007ffdc1450600 RCX: 00007f8235867357
[  108.424878] RDX: 00007ffdc14505a0 RSI: 0000000040406469 RDI: 0000000000000003
[  108.424890] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000022
[  108.424903] R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000002
[  108.424915] R13: 0000000000419101 R14: 00007ffdc1450600 R15: 00007ffdc14505f0
[  108.424928] Code: 45 b8 8b 4d c0 4c 89 f2 48 89 de ff d0 49 8b 07 4c 8b 45 b8 48 85 c0 75 dd 65 ff 0d d4 a1 c8 5f 0f 84 47 01 00 00 e9 0d fe ff ff <0f> 0b 45 31 f6 4c 8b 65 c8 49 8b 04 24 4d 39 ec 49 8d 9c 24 28
[  108.425055] RIP: i915_gem_evict_for_node+0x237/0x410 [i915] RSP: ffffc90000a17a58

Fixes: 172ae5b4c8c1 ("drm/i915: Fix i915_gem_evict_for_vma (soft-pinning)")
Fixes: 606fec956c0e ("drm/i915: Prefer random replacement before eviction search")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170111182132.19174-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
When marking the debugobject as freed, be sure that write is flushed
before another CPU may see it on a reallocation path.

Only seen once in CI:

[  159.240873] WARNING: CPU: 3 PID: 6735 at lib/debugobjects.c:263 debug_print_object+0x87/0xb0
[  159.240897] ODEBUG: init destroyed (active state 0) object type: i915_sw_fence hint: submit_notify+0x0/0x4c [i915]
[  159.240902] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul snd_hda_codec_realtek crc32_pclmul snd_hda_codec_generic snd_hda_codec_hdmi ghash_clmulni_intel snd_hda_codec snd_hwdep snd_hda_core snd_pcm mei_me lpc_ich mei e1000e ptp pps_core [last unloaded: i915]
[  159.240913] CPU: 3 PID: 6735 Comm: gem_exec_nop Tainted: G     U          4.10.0-rc3-CI-Trybot_479+ #1
[  159.240913] Hardware name: LENOVO 10AGS00601/SHARKBAY, BIOS FBKT34AUS 04/24/2013
[  159.240914] Call Trace:
[  159.240916]  dump_stack+0x67/0x92
[  159.240919]  __warn+0xc6/0xe0
[  159.240920]  warn_slowpath_fmt+0x4a/0x50
[  159.240921]  debug_print_object+0x87/0xb0
[  159.240935]  ? __i915_request_wait_for_execute+0x1d0/0x1d0 [i915]
[  159.240936]  __debug_object_init+0xb2/0x410
[  159.240950]  ? __i915_request_wait_for_execute+0x1d0/0x1d0 [i915]
[  159.240951]  debug_object_init+0x16/0x20
[  159.240962]  __i915_sw_fence_init+0x29/0x60 [i915]
[  159.240975]  i915_gem_request_alloc+0x1fb/0x450 [i915]
[  159.240987]  i915_gem_do_execbuffer.isra.15+0x798/0x1b20 [i915]
[  159.241000]  i915_gem_execbuffer2+0xc0/0x250 [i915]
[  159.241003]  drm_ioctl+0x200/0x450
[  159.241016]  ? i915_gem_execbuffer+0x330/0x330 [i915]
[  159.241018]  do_vfs_ioctl+0x90/0x6e0
[  159.241020]  ? trace_hardirqs_on_caller+0x122/0x1b0
[  159.241021]  SyS_ioctl+0x3c/0x70
[  159.241023]  entry_SYSCALL_64_fastpath+0x1c/0xb1
[  159.241024] RIP: 0033:0x7f9bc4f41357
[  159.241025] RSP: 002b:00007ffc6cd5c568 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[  159.241026] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9bc4f41357
[  159.241026] RDX: 00007ffc6cd5c640 RSI: 0000000040406469 RDI: 0000000000000003
[  159.241027] RBP: 00007ffc6cd5c640 R08: 0000000000047508 R09: 0000000000000001
[  159.241027] R10: 000b58552d323c3d R11: 0000000000000246 R12: 0000000040406469
[  159.241028] R13: 0000000000000003 R14: 0000000000000004 R15: 0000000000000001

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170113214335.5829-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
In function dispatch_workload(), if it fail before calling
intel_gvt_scan_and_shadow_wa_ctx(), the indirect ctx will
not be shadowed so no cleaup need. wa_ctx->indirect_ctx.obj
indicate whether indirect_ctx is shadowed. The obj is null
if it is unshadowed.

BUG: unable to handle kernel NULL pointer dereference at
00000000000001a0
IP: complete_execlist_workload+0x2c9/0x3e0 [i915]
Oops: 0002 [#1] SMP
task: ffff939546d2d880 task.stack: ffffbd9b82ac4000
RIP: 0010:complete_execlist_workload+0x2c9/0x3e0 [i915]
RSP: 0018:ffffbd9b82ac7dd8 EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff9393c725b540 RCX: 0000000000000006
RDX: 0000000000000007 RSI: 0000000000000202 RDI: ffff939559c8dd00
RBP: ffffbd9b82ac7e18 R08: 0000000000000001 R09: 000000000120dd8f
R10: 0000000000000000 R11: 000000000120dd8f R12: ffff9393c725b540
R13: ffff9393c725b618 R14: ffffbd9b81f0d000 R15: ffff939520e0e000
FS:  0000000000000000(0000) GS:ffff939559c80000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000001a0 CR3: 000000043d664000 CR4: 00000000003426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 workload_thread+0x312/0xd70 [i915]
 ? __wake_up_sync+0x20/0x20
 ? wake_atomic_t_function+0x60/0x60
 kthread+0x101/0x140

Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue Sep 19, 2017
The rcu_barrier() takes the cpu_hotplug mutex which itself is not
reclaim-safe, and so rcu_barrier() is illegal from inside the shrinker.

[  309.661373] =========================================================
[  309.661376] [ INFO: possible irq lock inversion dependency detected ]
[  309.661380] 4.11.0-rc1-CI-CI_DRM_2333+ #1 Tainted: G        W
[  309.661383] ---------------------------------------------------------
[  309.661386] gem_exec_gttfil/6435 just changed the state of lock:
[  309.661389]  (rcu_preempt_state.barrier_mutex){+.+.-.}, at: [<ffffffff81100731>] _rcu_barrier+0x31/0x160
[  309.661399] but this lock took another, RECLAIM_FS-unsafe lock in the past:
[  309.661402]  (cpu_hotplug.lock){+.+.+.}
[  309.661404]

               and interrupts could create inverse lock ordering between them.

[  309.661410]
               other info that might help us debug this:
[  309.661414]  Possible interrupt unsafe locking scenario:

[  309.661417]        CPU0                    CPU1
[  309.661419]        ----                    ----
[  309.661421]   lock(cpu_hotplug.lock);
[  309.661425]                                local_irq_disable();
[  309.661432]                                lock(rcu_preempt_state.barrier_mutex);
[  309.661441]                                lock(cpu_hotplug.lock);
[  309.661446]   <Interrupt>
[  309.661448]     lock(rcu_preempt_state.barrier_mutex);
[  309.661453]
                *** DEADLOCK ***

[  309.661460] 4 locks held by gem_exec_gttfil/6435:
[  309.661464]  #0:  (sb_writers#10){.+.+.+}, at: [<ffffffff8120d83d>] vfs_write+0x17d/0x1f0
[  309.661475]  #1:  (debugfs_srcu){......}, at: [<ffffffff81320491>] debugfs_use_file_start+0x41/0xa0
[  309.661486]  #2:  (&attr->mutex){+.+.+.}, at: [<ffffffff8123a3e7>] simple_attr_write+0x37/0xe0
[  309.661495]  #3:  (&dev->struct_mutex){+.+.+.}, at: [<ffffffffa0091b4a>] i915_drop_caches_set+0x3a/0x150 [i915]
[  309.661540]
               the shortest dependencies between 2nd lock and 1st lock:
[  309.661547]  -> (cpu_hotplug.lock){+.+.+.} ops: 829 {
[  309.661553]     HARDIRQ-ON-W at:
[  309.661560]                       __lock_acquire+0x5e5/0x1b50
[  309.661565]                       lock_acquire+0xc9/0x220
[  309.661572]                       __mutex_lock+0x6e/0x990
[  309.661576]                       mutex_lock_nested+0x16/0x20
[  309.661583]                       get_online_cpus+0x61/0x80
[  309.661590]                       kmem_cache_create+0x25/0x1d0
[  309.661596]                       debug_objects_mem_init+0x30/0x249
[  309.661602]                       start_kernel+0x341/0x3fe
[  309.661607]                       x86_64_start_reservations+0x2a/0x2c
[  309.661612]                       x86_64_start_kernel+0x173/0x186
[  309.661619]                       verify_cpu+0x0/0xfc
[  309.661622]     SOFTIRQ-ON-W at:
[  309.661627]                       __lock_acquire+0x611/0x1b50
[  309.661632]                       lock_acquire+0xc9/0x220
[  309.661636]                       __mutex_lock+0x6e/0x990
[  309.661641]                       mutex_lock_nested+0x16/0x20
[  309.661646]                       get_online_cpus+0x61/0x80
[  309.661650]                       kmem_cache_create+0x25/0x1d0
[  309.661655]                       debug_objects_mem_init+0x30/0x249
[  309.661660]                       start_kernel+0x341/0x3fe
[  309.661664]                       x86_64_start_reservations+0x2a/0x2c
[  309.661669]                       x86_64_start_kernel+0x173/0x186
[  309.661674]                       verify_cpu+0x0/0xfc
[  309.661677]     RECLAIM_FS-ON-W at:
[  309.661682]                          mark_held_locks+0x6f/0xa0
[  309.661687]                          lockdep_trace_alloc+0xb3/0x100
[  309.661693]                          kmem_cache_alloc_trace+0x31/0x2e0
[  309.661699]                          __smpboot_create_thread.part.1+0x27/0xe0
[  309.661704]                          smpboot_create_threads+0x61/0x90
[  309.661709]                          cpuhp_invoke_callback+0x9c/0x8a0
[  309.661713]                          cpuhp_up_callbacks+0x31/0xb0
[  309.661718]                          _cpu_up+0x7a/0xc0
[  309.661723]                          do_cpu_up+0x5f/0x80
[  309.661727]                          cpu_up+0xe/0x10
[  309.661734]                          smp_init+0x71/0xb3
[  309.661738]                          kernel_init_freeable+0x94/0x19e
[  309.661743]                          kernel_init+0x9/0xf0
[  309.661748]                          ret_from_fork+0x2e/0x40
[  309.661752]     INITIAL USE at:
[  309.661757]                      __lock_acquire+0x234/0x1b50
[  309.661761]                      lock_acquire+0xc9/0x220
[  309.661766]                      __mutex_lock+0x6e/0x990
[  309.661771]                      mutex_lock_nested+0x16/0x20
[  309.661775]                      get_online_cpus+0x61/0x80
[  309.661780]                      __cpuhp_setup_state+0x44/0x170
[  309.661785]                      page_alloc_init+0x23/0x3a
[  309.661790]                      start_kernel+0x124/0x3fe
[  309.661794]                      x86_64_start_reservations+0x2a/0x2c
[  309.661799]                      x86_64_start_kernel+0x173/0x186
[  309.661804]                      verify_cpu+0x0/0xfc
[  309.661807]   }
[  309.661813]   ... key      at: [<ffffffff81e37690>] cpu_hotplug+0xb0/0x100
[  309.661817]   ... acquired at:
[  309.661821]    lock_acquire+0xc9/0x220
[  309.661825]    __mutex_lock+0x6e/0x990
[  309.661829]    mutex_lock_nested+0x16/0x20
[  309.661833]    get_online_cpus+0x61/0x80
[  309.661837]    _rcu_barrier+0x9f/0x160
[  309.661841]    rcu_barrier+0x10/0x20
[  309.661847]    netdev_run_todo+0x5f/0x310
[  309.661852]    rtnl_unlock+0x9/0x10
[  309.661856]    default_device_exit_batch+0x133/0x150
[  309.661862]    ops_exit_list.isra.0+0x4d/0x60
[  309.661866]    cleanup_net+0x1d8/0x2c0
[  309.661872]    process_one_work+0x1f4/0x6d0
[  309.661876]    worker_thread+0x49/0x4a0
[  309.661881]    kthread+0x107/0x140
[  309.661884]    ret_from_fork+0x2e/0x40

[  309.661890] -> (rcu_preempt_state.barrier_mutex){+.+.-.} ops: 179 {
[  309.661896]    HARDIRQ-ON-W at:
[  309.661901]                     __lock_acquire+0x5e5/0x1b50
[  309.661905]                     lock_acquire+0xc9/0x220
[  309.661910]                     __mutex_lock+0x6e/0x990
[  309.661914]                     mutex_lock_nested+0x16/0x20
[  309.661919]                     _rcu_barrier+0x31/0x160
[  309.661923]                     rcu_barrier+0x10/0x20
[  309.661928]                     netdev_run_todo+0x5f/0x310
[  309.661932]                     rtnl_unlock+0x9/0x10
[  309.661936]                     default_device_exit_batch+0x133/0x150
[  309.661941]                     ops_exit_list.isra.0+0x4d/0x60
[  309.661946]                     cleanup_net+0x1d8/0x2c0
[  309.661951]                     process_one_work+0x1f4/0x6d0
[  309.661955]                     worker_thread+0x49/0x4a0
[  309.661960]                     kthread+0x107/0x140
[  309.661964]                     ret_from_fork+0x2e/0x40
[  309.661968]    SOFTIRQ-ON-W at:
[  309.661972]                     __lock_acquire+0x611/0x1b50
[  309.661977]                     lock_acquire+0xc9/0x220
[  309.661981]                     __mutex_lock+0x6e/0x990
[  309.661986]                     mutex_lock_nested+0x16/0x20
[  309.661990]                     _rcu_barrier+0x31/0x160
[  309.661995]                     rcu_barrier+0x10/0x20
[  309.661999]                     netdev_run_todo+0x5f/0x310
[  309.662003]                     rtnl_unlock+0x9/0x10
[  309.662008]                     default_device_exit_batch+0x133/0x150
[  309.662013]                     ops_exit_list.isra.0+0x4d/0x60
[  309.662017]                     cleanup_net+0x1d8/0x2c0
[  309.662022]                     process_one_work+0x1f4/0x6d0
[  309.662027]                     worker_thread+0x49/0x4a0
[  309.662031]                     kthread+0x107/0x140
[  309.662035]                     ret_from_fork+0x2e/0x40
[  309.662039]    IN-RECLAIM_FS-W at:
[  309.662043]                        __lock_acquire+0x638/0x1b50
[  309.662048]                        lock_acquire+0xc9/0x220
[  309.662053]                        __mutex_lock+0x6e/0x990
[  309.662058]                        mutex_lock_nested+0x16/0x20
[  309.662062]                        _rcu_barrier+0x31/0x160
[  309.662067]                        rcu_barrier+0x10/0x20
[  309.662089]                        i915_gem_shrink_all+0x33/0x40 [i915]
[  309.662109]                        i915_drop_caches_set+0x141/0x150 [i915]
[  309.662114]                        simple_attr_write+0xc7/0xe0
[  309.662119]                        full_proxy_write+0x4f/0x70
[  309.662124]                        __vfs_write+0x23/0x120
[  309.662128]                        vfs_write+0xc6/0x1f0
[  309.662133]                        SyS_write+0x44/0xb0
[  309.662138]                        entry_SYSCALL_64_fastpath+0x1c/0xb1
[  309.662142]    INITIAL USE at:
[  309.662147]                    __lock_acquire+0x234/0x1b50
[  309.662151]                    lock_acquire+0xc9/0x220
[  309.662156]                    __mutex_lock+0x6e/0x990
[  309.662160]                    mutex_lock_nested+0x16/0x20
[  309.662165]                    _rcu_barrier+0x31/0x160
[  309.662169]                    rcu_barrier+0x10/0x20
[  309.662174]                    netdev_run_todo+0x5f/0x310
[  309.662178]                    rtnl_unlock+0x9/0x10
[  309.662183]                    default_device_exit_batch+0x133/0x150
[  309.662188]                    ops_exit_list.isra.0+0x4d/0x60
[  309.662192]                    cleanup_net+0x1d8/0x2c0
[  309.662197]                    process_one_work+0x1f4/0x6d0
[  309.662202]                    worker_thread+0x49/0x4a0
[  309.662206]                    kthread+0x107/0x140
[  309.662210]                    ret_from_fork+0x2e/0x40
[  309.662214]  }
[  309.662220]  ... key      at: [<ffffffff81e4e1c8>] rcu_preempt_state+0x508/0x780
[  309.662225]  ... acquired at:
[  309.662229]    check_usage_forwards+0x12b/0x130
[  309.662233]    mark_lock+0x360/0x6f0
[  309.662237]    __lock_acquire+0x638/0x1b50
[  309.662241]    lock_acquire+0xc9/0x220
[  309.662245]    __mutex_lock+0x6e/0x990
[  309.662249]    mutex_lock_nested+0x16/0x20
[  309.662253]    _rcu_barrier+0x31/0x160
[  309.662257]    rcu_barrier+0x10/0x20
[  309.662279]    i915_gem_shrink_all+0x33/0x40 [i915]
[  309.662298]    i915_drop_caches_set+0x141/0x150 [i915]
[  309.662303]    simple_attr_write+0xc7/0xe0
[  309.662307]    full_proxy_write+0x4f/0x70
[  309.662311]    __vfs_write+0x23/0x120
[  309.662315]    vfs_write+0xc6/0x1f0
[  309.662319]    SyS_write+0x44/0xb0
[  309.662323]    entry_SYSCALL_64_fastpath+0x1c/0xb1

[  309.662329]
               stack backtrace:
[  309.662335] CPU: 1 PID: 6435 Comm: gem_exec_gttfil Tainted: G        W       4.11.0-rc1-CI-CI_DRM_2333+ #1
[  309.662342] Hardware name: Hewlett-Packard HP Compaq 8100 Elite SFF PC/304Ah, BIOS 786H1 v01.13 07/14/2011
[  309.662348] Call Trace:
[  309.662354]  dump_stack+0x67/0x92
[  309.662359]  print_irq_inversion_bug.part.19+0x1a4/0x1b0
[  309.662365]  check_usage_forwards+0x12b/0x130
[  309.662369]  mark_lock+0x360/0x6f0
[  309.662374]  ? print_shortest_lock_dependencies+0x1a0/0x1a0
[  309.662379]  __lock_acquire+0x638/0x1b50
[  309.662383]  ? __mutex_unlock_slowpath+0x3e/0x2e0
[  309.662388]  ? trace_hardirqs_on+0xd/0x10
[  309.662392]  ? _rcu_barrier+0x31/0x160
[  309.662396]  lock_acquire+0xc9/0x220
[  309.662400]  ? _rcu_barrier+0x31/0x160
[  309.662404]  ? _rcu_barrier+0x31/0x160
[  309.662409]  __mutex_lock+0x6e/0x990
[  309.662412]  ? _rcu_barrier+0x31/0x160
[  309.662416]  ? _rcu_barrier+0x31/0x160
[  309.662421]  ? synchronize_rcu_expedited+0x35/0xb0
[  309.662426]  ? _raw_spin_unlock_irqrestore+0x52/0x60
[  309.662434]  mutex_lock_nested+0x16/0x20
[  309.662438]  _rcu_barrier+0x31/0x160
[  309.662442]  rcu_barrier+0x10/0x20
[  309.662464]  i915_gem_shrink_all+0x33/0x40 [i915]
[  309.662484]  i915_drop_caches_set+0x141/0x150 [i915]
[  309.662489]  simple_attr_write+0xc7/0xe0
[  309.662494]  full_proxy_write+0x4f/0x70
[  309.662498]  __vfs_write+0x23/0x120
[  309.662503]  ? rcu_read_lock_sched_held+0x75/0x80
[  309.662507]  ? rcu_sync_lockdep_assert+0x2a/0x50
[  309.662512]  ? __sb_start_write+0x102/0x210
[  309.662516]  ? vfs_write+0x17d/0x1f0
[  309.662520]  vfs_write+0xc6/0x1f0
[  309.662524]  ? trace_hardirqs_on_caller+0xe7/0x200
[  309.662529]  SyS_write+0x44/0xb0
[  309.662533]  entry_SYSCALL_64_fastpath+0x1c/0xb1
[  309.662537] RIP: 0033:0x7f507eac24a0
[  309.662541] RSP: 002b:00007fffda8720e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  309.662548] RAX: ffffffffffffffda RBX: ffffffff81482bd3 RCX: 00007f507eac24a0
[  309.662552] RDX: 0000000000000005 RSI: 00007fffda8720f0 RDI: 0000000000000005
[  309.662557] RBP: ffffc9000048bf88 R08: 0000000000000000 R09: 000000000000002c
[  309.662561] R10: 0000000000000014 R11: 0000000000000246 R12: 00007fffda872230
[  309.662566] R13: 00007fffda872228 R14: 0000000000000201 R15: 00007fffda8720f0
[  309.662572]  ? __this_cpu_preempt_check+0x13/0x20

Fixes: 0eafec6d3244 ("drm/i915: Enable lockless lookup of request tracking via RCU")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100192
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: <stable@vger.kernel.org> # v4.9+
Link: http://patchwork.freedesktop.org/patch/msgid/20170314115019.18127-1-chris@chris-wilson.co.uk
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit bd784b7cc41af7a19cfb705fa6d800e511c4ab02)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170321144531.12344-1-chris@chris-wilson.co.uk
Signed-off-by: Johannes Lundberg <johalun0@gmail.com>
johalun pushed a commit that referenced this issue May 14, 2018
Before this change, the VGA palette was configured to match the shell
palette (e.g. color #1 was red). There was one glitch early in boot when
the vt(4)'s VGA palette was loaded: the loader's logo would switch from
red to blue. Likewise for the "Booting..." message switching from blue
to red. That's because the loader's logo was drawed with the default VGA
palette where a few colors are swapped compared to the shell palette
(e.g. blue <-> red).

This change configures the default VGA palette during initialization and
converts input's colors from shell to VGA palette index.

There should be no visible changes, except the loader's logo which will
keep its original color.

Reviewed by:	eadler
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