| Message ID | 20230606030037.196558-1-zhanjun.dong@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/i915: Avoid circular locking dependency when flush delayed work on gt reset | expand |
On 6/5/2023 20:00, Zhanjun Dong wrote: > This attemps to avoid circular locing dependency between flush delayed work and intel_gt_reset. locing -> locking > > WARNING: possible circular locking dependency detected > 6.4.0-rc1-drmtip_1340-g31e3463b0edb+ #1 Not tainted > ------------------------------------------------------ > kms_pipe_crc_ba/6415 is trying to acquire lock: > ffff88813e6cc640 ((work_completion)(&(&guc->timestamp.work)->work)){+.+.}-{0:0}, at: __flush_work+0x42/0x530 > > but task is already holding lock: > ffff88813e6cce90 (>->reset.mutex){+.+.}-{3:3}, at: intel_gt_reset+0x19e/0x470 [i915] > > which lock already depends on the new lock. > > the existing dependency chain (in reverse order) is: > > -> #3 (>->reset.mutex){+.+.}-{3:3}: > lock_acquire+0xd8/0x2d0 > i915_gem_shrinker_taints_mutex+0x31/0x50 [i915] > intel_gt_init_reset+0x65/0x80 [i915] > intel_gt_common_init_early+0xe1/0x170 [i915] > intel_root_gt_init_early+0x48/0x60 [i915] > i915_driver_probe+0x671/0xcb0 [i915] > i915_pci_probe+0xdc/0x210 [i915] > pci_device_probe+0x95/0x120 > really_probe+0x164/0x3c0 > __driver_probe_device+0x73/0x160 > driver_probe_device+0x19/0xa0 > __driver_attach+0xb6/0x180 > bus_for_each_dev+0x77/0xd0 > bus_add_driver+0x114/0x210 > driver_register+0x5b/0x110 > __pfx_vgem_open+0x3/0x10 [vgem] > do_one_initcall+0x57/0x270 > do_init_module+0x5f/0x220 > load_module+0x1ca4/0x1f00 > __do_sys_finit_module+0xb4/0x130 > do_syscall_64+0x3c/0x90 > entry_SYSCALL_64_after_hwframe+0x72/0xdc > > -> #2 (fs_reclaim){+.+.}-{0:0}: > lock_acquire+0xd8/0x2d0 > fs_reclaim_acquire+0xac/0xe0 > kmem_cache_alloc+0x32/0x260 > i915_vma_instance+0xb2/0xc60 [i915] > i915_gem_object_ggtt_pin_ww+0x175/0x370 [i915] > vm_fault_gtt+0x22d/0xf60 [i915] > __do_fault+0x2f/0x1d0 > do_pte_missing+0x4a/0xd20 > __handle_mm_fault+0x5b0/0x790 > handle_mm_fault+0xa2/0x230 > do_user_addr_fault+0x3ea/0xa10 > exc_page_fault+0x68/0x1a0 > asm_exc_page_fault+0x26/0x30 > > -> #1 (>->reset.backoff_srcu){++++}-{0:0}: > lock_acquire+0xd8/0x2d0 > _intel_gt_reset_lock+0x57/0x330 [i915] > guc_timestamp_ping+0x35/0x130 [i915] > process_one_work+0x250/0x510 > worker_thread+0x4f/0x3a0 > kthread+0xff/0x130 > ret_from_fork+0x29/0x50 > > -> #0 ((work_completion)(&(&guc->timestamp.work)->work)){+.+.}-{0:0}: > check_prev_add+0x90/0xc60 > __lock_acquire+0x1998/0x2590 > lock_acquire+0xd8/0x2d0 > __flush_work+0x74/0x530 > __cancel_work_timer+0x14f/0x1f0 > intel_guc_submission_reset_prepare+0x81/0x4b0 [i915] > intel_uc_reset_prepare+0x9c/0x120 [i915] > reset_prepare+0x21/0x60 [i915] > intel_gt_reset+0x1dd/0x470 [i915] > intel_gt_reset_global+0xfb/0x170 [i915] > intel_gt_handle_error+0x368/0x420 [i915] > intel_gt_debugfs_reset_store+0x5c/0xc0 [i915] > i915_wedged_set+0x29/0x40 [i915] > simple_attr_write_xsigned.constprop.0+0xb4/0x110 > full_proxy_write+0x52/0x80 > vfs_write+0xc5/0x4f0 > ksys_write+0x64/0xe0 > do_syscall_64+0x3c/0x90 > entry_SYSCALL_64_after_hwframe+0x72/0xdc > > other info that might help us debug this: > Chain exists of: > (work_completion)(&(&guc->timestamp.work)->work) --> fs_reclaim --> >->reset.mutex > Possible unsafe locking scenario: > CPU0 CPU1 > ---- ---- > lock(>->reset.mutex); > lock(fs_reclaim); > lock(>->reset.mutex); > lock((work_completion)(&(&guc->timestamp.work)->work)); > > *** DEADLOCK *** > 3 locks held by kms_pipe_crc_ba/6415: > #0: ffff888101541430 (sb_writers#15){.+.+}-{0:0}, at: ksys_write+0x64/0xe0 > #1: ffff888136c7eab8 (&attr->mutex){+.+.}-{3:3}, at: simple_attr_write_xsigned.constprop.0+0x47/0x110 > #2: ffff88813e6cce90 (>->reset.mutex){+.+.}-{3:3}, at: intel_gt_reset+0x19e/0x470 [i915] > > Signed-off-by: Zhanjun Dong <zhanjun.dong@intel.com> > --- > drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > index a0e3ef1c65d2..22390704542e 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > @@ -1359,7 +1359,7 @@ static void guc_enable_busyness_worker(struct intel_guc *guc) > > static void guc_cancel_busyness_worker(struct intel_guc *guc) > { > - cancel_delayed_work_sync(&guc->timestamp.work); > + cancel_delayed_work(&guc->timestamp.work); I think it is worth adding a comment here to explain that it is safe to call the non _sync variant (because of the trylock code in the worker itself) and that the _sync variant hits circular mutex lock issues. John. > } > > static void __reset_guc_busyness_stats(struct intel_guc *guc)
On 06.06.2023 05:00, Zhanjun Dong wrote: > This attemps to avoid circular locing dependency between flush delayed work and intel_gt_reset. > > WARNING: possible circular locking dependency detected > 6.4.0-rc1-drmtip_1340-g31e3463b0edb+ #1 Not tainted > ------------------------------------------------------ > kms_pipe_crc_ba/6415 is trying to acquire lock: > ffff88813e6cc640 ((work_completion)(&(&guc->timestamp.work)->work)){+.+.}-{0:0}, at: __flush_work+0x42/0x530 > > but task is already holding lock: > ffff88813e6cce90 (>->reset.mutex){+.+.}-{3:3}, at: intel_gt_reset+0x19e/0x470 [i915] > > which lock already depends on the new lock. > > the existing dependency chain (in reverse order) is: > > -> #3 (>->reset.mutex){+.+.}-{3:3}: > lock_acquire+0xd8/0x2d0 > i915_gem_shrinker_taints_mutex+0x31/0x50 [i915] > intel_gt_init_reset+0x65/0x80 [i915] > intel_gt_common_init_early+0xe1/0x170 [i915] > intel_root_gt_init_early+0x48/0x60 [i915] > i915_driver_probe+0x671/0xcb0 [i915] > i915_pci_probe+0xdc/0x210 [i915] > pci_device_probe+0x95/0x120 > really_probe+0x164/0x3c0 > __driver_probe_device+0x73/0x160 > driver_probe_device+0x19/0xa0 > __driver_attach+0xb6/0x180 > bus_for_each_dev+0x77/0xd0 > bus_add_driver+0x114/0x210 > driver_register+0x5b/0x110 > __pfx_vgem_open+0x3/0x10 [vgem] > do_one_initcall+0x57/0x270 > do_init_module+0x5f/0x220 > load_module+0x1ca4/0x1f00 > __do_sys_finit_module+0xb4/0x130 > do_syscall_64+0x3c/0x90 > entry_SYSCALL_64_after_hwframe+0x72/0xdc > > -> #2 (fs_reclaim){+.+.}-{0:0}: > lock_acquire+0xd8/0x2d0 > fs_reclaim_acquire+0xac/0xe0 > kmem_cache_alloc+0x32/0x260 > i915_vma_instance+0xb2/0xc60 [i915] > i915_gem_object_ggtt_pin_ww+0x175/0x370 [i915] > vm_fault_gtt+0x22d/0xf60 [i915] > __do_fault+0x2f/0x1d0 > do_pte_missing+0x4a/0xd20 > __handle_mm_fault+0x5b0/0x790 > handle_mm_fault+0xa2/0x230 > do_user_addr_fault+0x3ea/0xa10 > exc_page_fault+0x68/0x1a0 > asm_exc_page_fault+0x26/0x30 > > -> #1 (>->reset.backoff_srcu){++++}-{0:0}: > lock_acquire+0xd8/0x2d0 > _intel_gt_reset_lock+0x57/0x330 [i915] > guc_timestamp_ping+0x35/0x130 [i915] > process_one_work+0x250/0x510 > worker_thread+0x4f/0x3a0 > kthread+0xff/0x130 > ret_from_fork+0x29/0x50 > > -> #0 ((work_completion)(&(&guc->timestamp.work)->work)){+.+.}-{0:0}: > check_prev_add+0x90/0xc60 > __lock_acquire+0x1998/0x2590 > lock_acquire+0xd8/0x2d0 > __flush_work+0x74/0x530 > __cancel_work_timer+0x14f/0x1f0 > intel_guc_submission_reset_prepare+0x81/0x4b0 [i915] > intel_uc_reset_prepare+0x9c/0x120 [i915] > reset_prepare+0x21/0x60 [i915] > intel_gt_reset+0x1dd/0x470 [i915] > intel_gt_reset_global+0xfb/0x170 [i915] > intel_gt_handle_error+0x368/0x420 [i915] > intel_gt_debugfs_reset_store+0x5c/0xc0 [i915] > i915_wedged_set+0x29/0x40 [i915] > simple_attr_write_xsigned.constprop.0+0xb4/0x110 > full_proxy_write+0x52/0x80 > vfs_write+0xc5/0x4f0 > ksys_write+0x64/0xe0 > do_syscall_64+0x3c/0x90 > entry_SYSCALL_64_after_hwframe+0x72/0xdc > > other info that might help us debug this: > Chain exists of: > (work_completion)(&(&guc->timestamp.work)->work) --> fs_reclaim --> >->reset.mutex > Possible unsafe locking scenario: > CPU0 CPU1 > ---- ---- > lock(>->reset.mutex); > lock(fs_reclaim); > lock(>->reset.mutex); > lock((work_completion)(&(&guc->timestamp.work)->work)); > > *** DEADLOCK *** > 3 locks held by kms_pipe_crc_ba/6415: > #0: ffff888101541430 (sb_writers#15){.+.+}-{0:0}, at: ksys_write+0x64/0xe0 > #1: ffff888136c7eab8 (&attr->mutex){+.+.}-{3:3}, at: simple_attr_write_xsigned.constprop.0+0x47/0x110 > #2: ffff88813e6cce90 (>->reset.mutex){+.+.}-{3:3}, at: intel_gt_reset+0x19e/0x470 [i915] > > Signed-off-by: Zhanjun Dong <zhanjun.dong@intel.com> This unlocks multiple machines on CI, thx. Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com> Regards Andrzej > --- > drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > index a0e3ef1c65d2..22390704542e 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c > @@ -1359,7 +1359,7 @@ static void guc_enable_busyness_worker(struct intel_guc *guc) > > static void guc_cancel_busyness_worker(struct intel_guc *guc) > { > - cancel_delayed_work_sync(&guc->timestamp.work); > + cancel_delayed_work(&guc->timestamp.work); > } > > static void __reset_guc_busyness_stats(struct intel_guc *guc)
On 6/6/2023 10:53, John Harrison wrote: > On 6/5/2023 20:00, Zhanjun Dong wrote: >> This attemps to avoid circular locing dependency between flush >> delayed work and intel_gt_reset. > locing -> locking > > >> >> WARNING: possible circular locking dependency detected >> 6.4.0-rc1-drmtip_1340-g31e3463b0edb+ #1 Not tainted >> ------------------------------------------------------ >> kms_pipe_crc_ba/6415 is trying to acquire lock: >> ffff88813e6cc640 >> ((work_completion)(&(&guc->timestamp.work)->work)){+.+.}-{0:0}, at: >> __flush_work+0x42/0x530 >> >> but task is already holding lock: >> ffff88813e6cce90 (>->reset.mutex){+.+.}-{3:3}, at: >> intel_gt_reset+0x19e/0x470 [i915] >> >> which lock already depends on the new lock. >> >> the existing dependency chain (in reverse order) is: >> >> -> #3 (>->reset.mutex){+.+.}-{3:3}: >> lock_acquire+0xd8/0x2d0 >> i915_gem_shrinker_taints_mutex+0x31/0x50 [i915] >> intel_gt_init_reset+0x65/0x80 [i915] >> intel_gt_common_init_early+0xe1/0x170 [i915] >> intel_root_gt_init_early+0x48/0x60 [i915] >> i915_driver_probe+0x671/0xcb0 [i915] >> i915_pci_probe+0xdc/0x210 [i915] >> pci_device_probe+0x95/0x120 >> really_probe+0x164/0x3c0 >> __driver_probe_device+0x73/0x160 >> driver_probe_device+0x19/0xa0 >> __driver_attach+0xb6/0x180 >> bus_for_each_dev+0x77/0xd0 >> bus_add_driver+0x114/0x210 >> driver_register+0x5b/0x110 >> __pfx_vgem_open+0x3/0x10 [vgem] >> do_one_initcall+0x57/0x270 >> do_init_module+0x5f/0x220 >> load_module+0x1ca4/0x1f00 >> __do_sys_finit_module+0xb4/0x130 >> do_syscall_64+0x3c/0x90 >> entry_SYSCALL_64_after_hwframe+0x72/0xdc >> >> -> #2 (fs_reclaim){+.+.}-{0:0}: >> lock_acquire+0xd8/0x2d0 >> fs_reclaim_acquire+0xac/0xe0 >> kmem_cache_alloc+0x32/0x260 >> i915_vma_instance+0xb2/0xc60 [i915] >> i915_gem_object_ggtt_pin_ww+0x175/0x370 [i915] >> vm_fault_gtt+0x22d/0xf60 [i915] >> __do_fault+0x2f/0x1d0 >> do_pte_missing+0x4a/0xd20 >> __handle_mm_fault+0x5b0/0x790 >> handle_mm_fault+0xa2/0x230 >> do_user_addr_fault+0x3ea/0xa10 >> exc_page_fault+0x68/0x1a0 >> asm_exc_page_fault+0x26/0x30 >> >> -> #1 (>->reset.backoff_srcu){++++}-{0:0}: >> lock_acquire+0xd8/0x2d0 >> _intel_gt_reset_lock+0x57/0x330 [i915] >> guc_timestamp_ping+0x35/0x130 [i915] >> process_one_work+0x250/0x510 >> worker_thread+0x4f/0x3a0 >> kthread+0xff/0x130 >> ret_from_fork+0x29/0x50 >> >> -> #0 ((work_completion)(&(&guc->timestamp.work)->work)){+.+.}-{0:0}: >> check_prev_add+0x90/0xc60 >> __lock_acquire+0x1998/0x2590 >> lock_acquire+0xd8/0x2d0 >> __flush_work+0x74/0x530 >> __cancel_work_timer+0x14f/0x1f0 >> intel_guc_submission_reset_prepare+0x81/0x4b0 [i915] >> intel_uc_reset_prepare+0x9c/0x120 [i915] >> reset_prepare+0x21/0x60 [i915] >> intel_gt_reset+0x1dd/0x470 [i915] >> intel_gt_reset_global+0xfb/0x170 [i915] >> intel_gt_handle_error+0x368/0x420 [i915] >> intel_gt_debugfs_reset_store+0x5c/0xc0 [i915] >> i915_wedged_set+0x29/0x40 [i915] >> simple_attr_write_xsigned.constprop.0+0xb4/0x110 >> full_proxy_write+0x52/0x80 >> vfs_write+0xc5/0x4f0 >> ksys_write+0x64/0xe0 >> do_syscall_64+0x3c/0x90 >> entry_SYSCALL_64_after_hwframe+0x72/0xdc >> >> other info that might help us debug this: >> Chain exists of: >> (work_completion)(&(&guc->timestamp.work)->work) --> fs_reclaim --> >> >->reset.mutex >> Possible unsafe locking scenario: >> CPU0 CPU1 >> ---- ---- >> lock(>->reset.mutex); >> lock(fs_reclaim); >> lock(>->reset.mutex); >> lock((work_completion)(&(&guc->timestamp.work)->work)); >> >> *** DEADLOCK *** >> 3 locks held by kms_pipe_crc_ba/6415: >> #0: ffff888101541430 (sb_writers#15){.+.+}-{0:0}, at: >> ksys_write+0x64/0xe0 >> #1: ffff888136c7eab8 (&attr->mutex){+.+.}-{3:3}, at: >> simple_attr_write_xsigned.constprop.0+0x47/0x110 >> #2: ffff88813e6cce90 (>->reset.mutex){+.+.}-{3:3}, at: >> intel_gt_reset+0x19e/0x470 [i915] >> >> Signed-off-by: Zhanjun Dong <zhanjun.dong@intel.com> >> --- >> drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c >> b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c >> index a0e3ef1c65d2..22390704542e 100644 >> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c >> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c >> @@ -1359,7 +1359,7 @@ static void guc_enable_busyness_worker(struct >> intel_guc *guc) >> static void guc_cancel_busyness_worker(struct intel_guc *guc) >> { >> - cancel_delayed_work_sync(&guc->timestamp.work); >> + cancel_delayed_work(&guc->timestamp.work); > I think it is worth adding a comment here to explain that it is safe > to call the non _sync variant (because of the trylock code in the > worker itself) and that the _sync variant hits circular mutex lock > issues. > To record the notes from direct discussion... This function needs to take a 'bool sync' flag. The park/fini code paths still need to do a synchronous flush to ensure that the worker is not still running during suspend or shutdown. Only the reset path should do the asynchronous cancel. John. > John. > > >> } >> static void __reset_guc_busyness_stats(struct intel_guc *guc) >
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c index a0e3ef1c65d2..22390704542e 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -1359,7 +1359,7 @@ static void guc_enable_busyness_worker(struct intel_guc *guc) static void guc_cancel_busyness_worker(struct intel_guc *guc) { - cancel_delayed_work_sync(&guc->timestamp.work); + cancel_delayed_work(&guc->timestamp.work); } static void __reset_guc_busyness_stats(struct intel_guc *guc)
This attemps to avoid circular locing dependency between flush delayed work and intel_gt_reset. WARNING: possible circular locking dependency detected 6.4.0-rc1-drmtip_1340-g31e3463b0edb+ #1 Not tainted ------------------------------------------------------ kms_pipe_crc_ba/6415 is trying to acquire lock: ffff88813e6cc640 ((work_completion)(&(&guc->timestamp.work)->work)){+.+.}-{0:0}, at: __flush_work+0x42/0x530 but task is already holding lock: ffff88813e6cce90 (>->reset.mutex){+.+.}-{3:3}, at: intel_gt_reset+0x19e/0x470 [i915] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (>->reset.mutex){+.+.}-{3:3}: lock_acquire+0xd8/0x2d0 i915_gem_shrinker_taints_mutex+0x31/0x50 [i915] intel_gt_init_reset+0x65/0x80 [i915] intel_gt_common_init_early+0xe1/0x170 [i915] intel_root_gt_init_early+0x48/0x60 [i915] i915_driver_probe+0x671/0xcb0 [i915] i915_pci_probe+0xdc/0x210 [i915] pci_device_probe+0x95/0x120 really_probe+0x164/0x3c0 __driver_probe_device+0x73/0x160 driver_probe_device+0x19/0xa0 __driver_attach+0xb6/0x180 bus_for_each_dev+0x77/0xd0 bus_add_driver+0x114/0x210 driver_register+0x5b/0x110 __pfx_vgem_open+0x3/0x10 [vgem] do_one_initcall+0x57/0x270 do_init_module+0x5f/0x220 load_module+0x1ca4/0x1f00 __do_sys_finit_module+0xb4/0x130 do_syscall_64+0x3c/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc -> #2 (fs_reclaim){+.+.}-{0:0}: lock_acquire+0xd8/0x2d0 fs_reclaim_acquire+0xac/0xe0 kmem_cache_alloc+0x32/0x260 i915_vma_instance+0xb2/0xc60 [i915] i915_gem_object_ggtt_pin_ww+0x175/0x370 [i915] vm_fault_gtt+0x22d/0xf60 [i915] __do_fault+0x2f/0x1d0 do_pte_missing+0x4a/0xd20 __handle_mm_fault+0x5b0/0x790 handle_mm_fault+0xa2/0x230 do_user_addr_fault+0x3ea/0xa10 exc_page_fault+0x68/0x1a0 asm_exc_page_fault+0x26/0x30 -> #1 (>->reset.backoff_srcu){++++}-{0:0}: lock_acquire+0xd8/0x2d0 _intel_gt_reset_lock+0x57/0x330 [i915] guc_timestamp_ping+0x35/0x130 [i915] process_one_work+0x250/0x510 worker_thread+0x4f/0x3a0 kthread+0xff/0x130 ret_from_fork+0x29/0x50 -> #0 ((work_completion)(&(&guc->timestamp.work)->work)){+.+.}-{0:0}: check_prev_add+0x90/0xc60 __lock_acquire+0x1998/0x2590 lock_acquire+0xd8/0x2d0 __flush_work+0x74/0x530 __cancel_work_timer+0x14f/0x1f0 intel_guc_submission_reset_prepare+0x81/0x4b0 [i915] intel_uc_reset_prepare+0x9c/0x120 [i915] reset_prepare+0x21/0x60 [i915] intel_gt_reset+0x1dd/0x470 [i915] intel_gt_reset_global+0xfb/0x170 [i915] intel_gt_handle_error+0x368/0x420 [i915] intel_gt_debugfs_reset_store+0x5c/0xc0 [i915] i915_wedged_set+0x29/0x40 [i915] simple_attr_write_xsigned.constprop.0+0xb4/0x110 full_proxy_write+0x52/0x80 vfs_write+0xc5/0x4f0 ksys_write+0x64/0xe0 do_syscall_64+0x3c/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc other info that might help us debug this: Chain exists of: (work_completion)(&(&guc->timestamp.work)->work) --> fs_reclaim --> >->reset.mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(>->reset.mutex); lock(fs_reclaim); lock(>->reset.mutex); lock((work_completion)(&(&guc->timestamp.work)->work)); *** DEADLOCK *** 3 locks held by kms_pipe_crc_ba/6415: #0: ffff888101541430 (sb_writers#15){.+.+}-{0:0}, at: ksys_write+0x64/0xe0 #1: ffff888136c7eab8 (&attr->mutex){+.+.}-{3:3}, at: simple_attr_write_xsigned.constprop.0+0x47/0x110 #2: ffff88813e6cce90 (>->reset.mutex){+.+.}-{3:3}, at: intel_gt_reset+0x19e/0x470 [i915] Signed-off-by: Zhanjun Dong <zhanjun.dong@intel.com> --- drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)