Hello everyone, I am a new kernel developer with the Red Hat real-time team.
I am seeing two different call traces with 6.4-rt6 on my 12th Gen Intel Framework Laptop with i915 emit the same bug. Both of them occurred in the same boot. This kernel was built and tested on RHEL8. [1] occurs only once. [2] occurs ~50 times in a boot and log in to the gnome desktop.
[1]
[ 3800.598054] BUG: sleeping function called from invalid context at drivers/gpu/drm/i915/gt/uc/intel_guc.h:329
[ 3800.598060] in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 207, name: kworker/4:1H
[ 3800.598063] preempt_count: 0, expected: 0
[ 3800.598065] RCU nest depth: 5, expected: 0
[ 3800.598066] 11 locks held by kworker/4:1H/207:
[ 3800.598069] #0: ffff93b400054f38 ((wq_completion)events_highpri){+.+.}-{0:0}, at: process_one_work (./include/linux/list.h:927 ./include/linux/hashtable.h:107 kernel/workqueue.c:2446)
[ 3800.598084] #1: ffffbc7441087e70 ((work_completion)(&(&engine->heartbeat.work)->work)){+.+.}-{0:0}, at: process_one_work (./include/linux/list.h:899 ./include/linux/list.h:927 ./include/linux/hashtable.h:107 kernel/workqueue.c:2446)
[ 3800.598093] #2: ffff93b401cfd470 (kernel_context){+.+.}-{3:3}, at: heartbeat (./include/linux/rcupdate.h:805 ./drivers/gpu/drm/i915/i915_request.h:622 drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c:148) i915
[ 3800.598247] #3: ffff93bb8cc207e0 ((softirq_ctrl.lock)){+.+.}-{2:2}, at: __local_bh_disable_ip (kernel/softirq.c:157 (discriminator 19))
[ 3800.598258] #4: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock (kernel/locking/spinlock_rt.c:95)
[ 3800.598268] #5: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: __local_bh_disable_ip (kernel/softirq.c:157 (discriminator 15))
[ 3800.598276] #6: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: submit_notify (./include/linux/rcupdate.h:805 drivers/gpu/drm/i915/i915_request.c:798) i915
[ 3800.598457] #7: ffff93b5a1ccaa68 (&sched_engine->lock/2){+.+.}-{2:2}, at: guc_submit_request (drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:1985 drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:2001) i915
[ 3800.598632] #8: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock (kernel/locking/spinlock_rt.c:95)
[ 3800.598639] #9: ffff93b5a1e4f6f0 (&ce->guc_state.lock){+.+.}-{2:2}, at: add_to_context (./include/linux/list.h:134 ./include/linux/list.h:229 drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:3408) i915
[ 3800.598801] #10: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock (kernel/locking/spinlock_rt.c:95)
[ 3800.598813] Hardware name: Framework Laptop (12th Gen Intel Core)/FRANGACP04, BIOS 03.04 07/15/2022
[ 3800.598816] Workqueue: events_highpri heartbeat [i915]
[ 3800.598935] Call Trace:
[ 3800.598937] <TASK>
[ 3800.598940] dump_stack_lvl (lib/dump_stack.c:113)
[ 3800.598947] __might_resched+0x1a0/0x260
[ 3800.598956] guc_context_set_prio (drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:3345 drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:4009) i915
[ 3800.599123] ? lock_is_held_type+0xe1/0x140
[ 3800.599133] add_to_context (drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:3386 drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:3430 drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:4034) i915
[ 3800.599300] __i915_request_submit (drivers/gpu/drm/i915/i915_request.c:199 drivers/gpu/drm/i915/i915_request.c:210 drivers/gpu/drm/i915/i915_request.c:691) i915
[ 3800.599460] guc_submit_request (drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:1966 drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:2003) i915
[ 3800.599622] submit_notify (./include/linux/refcount.h:199 ./include/linux/refcount.h:250 ./include/linux/refcount.h:267 ./include/linux/kref.h:45 ./include/linux/dma-fence.h:308 ./include/linux/dma-fence.h:305 ./drivers/gpu/drm/i915/i915_request.h:402 drivers/gpu/drm/i915/i915_request.c:309 drivers/gpu/drm/i915/i915_request.c:786) i915
[ 3800.599784] __i915_sw_fence_complete (drivers/gpu/drm/i915/i915_sw_fence.c:201) i915
[ 3800.599919] __i915_request_queue (./include/linux/bottom_half.h:33 drivers/gpu/drm/i915/i915_request.c:1832) i915
[ 3800.600108] heartbeat (drivers/gpu/drm/i915/gt/intel_engine_heartbeat.c:285) i915
[ 3800.600241] process_one_work (./arch/x86/include/asm/bitops.h:228 ./arch/x86/include/asm/bitops.h:240 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 ./include/linux/cpumask.h:504 ./include/linux/cpumask.h:1082 ./include/trace/events/workqueue.h:82 kernel/workqueue.c:2407)
[ 3800.600261] worker_thread (kernel/workqueue.c:2556)
[ 3800.600269] ? __pfx_worker_thread (kernel/workqueue.c:2498)
[ 3800.600273] kthread (kernel/kthread.c:348)
[ 3800.600278] ? __pfx_kthread (kernel/kthread.c:332)
[ 3800.600287] ret_from_fork (arch/x86/entry/entry_64.S:308)
[ 3800.600312] </TASK>
[2]
[ 3796.648741] BUG: sleeping function called from invalid context at drivers/gpu/drm/i915/gt/uc/intel_guc.h:329
[ 3796.648746] in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 47819, name: gnome-shell
[ 3796.648749] preempt_count: 0, expected: 0
[ 3796.648750] RCU nest depth: 6, expected: 0
[ 3796.648752] 12 locks held by gnome-shell/47819:
[ 3796.648824] #0: ffffbc74443b3d28 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_mode_page_flip_ioctl (drivers/gpu/drm/drm_plane.c:1342) drm
[ 3796.648887] #1: ffff93b4438e5088 (crtc_ww_class_mutex){+.+.}-{3:3}, at: drm_modeset_lock (drivers/gpu/drm/drm_modeset_lock.c:317) drm
[ 3796.648944] #2: ffff93bb8bc207e0 ((softirq_ctrl.lock)){+.+.}-{2:2}, at: __local_bh_disable_ip (kernel/softirq.c:157 (discriminator 19))
[ 3796.648954] #3: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock (kernel/locking/spinlock_rt.c:95)
[ 3796.648963] #4: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: __local_bh_disable_ip (kernel/softirq.c:157 (discriminator 15))
[ 3796.648971] #5: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: fence_set_priority (drivers/gpu/drm/i915/gem/i915_gem_wait.c:105 drivers/gpu/drm/i915/gem/i915_gem_wait.c:92) i915
[ 3796.649136] #6: ffffffffc0a4fa40 (schedule_lock){+.+.}-{2:2}, at: i915_schedule (drivers/gpu/drm/i915/i915_scheduler.c:163 drivers/gpu/drm/i915/i915_scheduler.c:292) i915
[ 3796.649279] #7: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock (kernel/locking/spinlock_rt.c:95)
[ 3796.649285] #8: ffff93b5a1ccaa68 (&sched_engine->lock/2){+.+.}-{2:2}, at: i915_schedule (drivers/gpu/drm/i915/i915_scheduler.c:294) i915
[ 3796.649425] #9: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock (kernel/locking/spinlock_rt.c:95)
[ 3796.649431] #10: ffff93b4405762b0 (&ce->guc_state.lock){+.+.}-{2:2}, at: guc_bump_inflight_request_prio (drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:4019) i915
[ 3796.649572] #11: ffffffff9fe21000 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock (kernel/locking/spinlock_rt.c:95)
[ 3796.649583] Hardware name: Framework Laptop (12th Gen Intel Core)/FRANGACP04, BIOS 03.04 07/15/2022
[ 3796.649584] Call Trace:
[ 3796.649586] <TASK>
[ 3796.649589] dump_stack_lvl (lib/dump_stack.c:113)
[ 3796.649596] __might_resched+0x1a0/0x260
[ 3796.649603] guc_context_set_prio (drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:3345 drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:4009) i915
[ 3796.649735] ? lock_is_held_type+0xe1/0x140
[ 3796.649743] guc_bump_inflight_request_prio (drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c:3385) i915
[ 3796.649904] i915_schedule (drivers/gpu/drm/i915/i915_scheduler.c:338) i915
[ 3796.650082] ? lock_release+0x15e/0x450
[ 3796.650101] fence_set_priority (drivers/gpu/drm/i915/gem/i915_gem_wait.c:70) i915
[ 3796.650274] i915_gem_fence_wait_priority (./include/linux/bottom_half.h:31 drivers/gpu/drm/i915/gem/i915_gem_wait.c:144 drivers/gpu/drm/i915/gem/i915_gem_wait.c:115) i915
[ 3796.650448] i915_gem_object_wait_priority (drivers/gpu/drm/i915/gem/i915_gem_wait.c:157 (discriminator 3)) i915
[ 3796.650617] intel_prepare_plane_fb (drivers/gpu/drm/i915/display/intel_atomic_plane.c:1077) i915
[ 3796.650783] ? is_module_address (./arch/x86/include/asm/preempt.h:121 kernel/module/main.c:3169)
[ 3796.650790] ? static_obj+0x5a/0x70
[ 3796.650802] drm_atomic_helper_prepare_planes (drivers/gpu/drm/drm_atomic_helper.c:2580 drivers/gpu/drm/drm_atomic_helper.c:2556) drm_kms_helper
[ 3796.650828] intel_atomic_commit (drivers/gpu/drm/i915/display/intel_display.c:6767 drivers/gpu/drm/i915/display/intel_display.c:7576) i915
[ 3796.650982] drm_atomic_helper_page_flip (./arch/x86/include/asm/atomic.h:190 ./include/linux/atomic/atomic-instrumented.h:177 ./include/linux/refcount.h:272 ./include/linux/refcount.h:315 ./include/linux/refcount.h:333 ./include/linux/kref.h:64 ./include/drm/drm_atomic.h:490 drivers/gpu/drm/drm_atomic_helper.c:3647) drm_kms_helper
[ 3796.651000] drm_mode_page_flip_ioctl (drivers/gpu/drm/drm_plane.c:1377) drm
[ 3796.651057] ? __pfx_drm_mode_page_flip_ioctl (drivers/gpu/drm/drm_plane.c:1213) drm
[ 3796.651094] drm_ioctl_kernel (drivers/gpu/drm/drm_ioctl.c:794) drm
[ 3796.651136] drm_ioctl (./include/linux/thread_info.h:277 ./include/linux/thread_info.h:313 ./include/linux/uaccess.h:190 drivers/gpu/drm/drm_ioctl.c:892) drm
[ 3796.651175] ? __pfx_drm_mode_page_flip_ioctl (drivers/gpu/drm/drm_plane.c:1213) drm
[ 3796.651210] ? lock_release+0xeb/0x450
[ 3796.651222] __x64_sys_ioctl (fs/ioctl.c:51 fs/ioctl.c:870 fs/ioctl.c:856 fs/ioctl.c:856)
[ 3796.651228] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
[ 3796.651233] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
[ 3796.651237] RIP: 0033:0x7fd3cc0fe7cb
