syzbot

INFO: task swapper/0:1 blocked for more than 143 seconds.
      Not tainted 6.15.0-rc2-syzkaller-00278-gfc96b232f8e7 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:swapper/0       state:D stack:18272 pid:1     tgid:1     ppid:0      task_flags:0x0140 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x1b88/0x5240 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x163/0x360 kernel/sched/core.c:6860
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
 __mutex_lock_common kernel/locking/mutex.c:678 [inline]
 __ww_mutex_lock+0x1131/0x2b10 kernel/locking/mutex.c:753
 ww_mutex_lock+0x40/0x200 kernel/locking/mutex.c:870
 modeset_lock+0x2c8/0x660 drivers/gpu/drm/drm_modeset_lock.c:314
 drm_atomic_get_plane_state+0x1c3/0x510 drivers/gpu/drm/drm_atomic.c:541
 drm_client_modeset_commit_atomic+0x19d/0x7d0 drivers/gpu/drm/drm_client_modeset.c:1031
 drm_client_modeset_commit_locked+0xe0/0x520 drivers/gpu/drm/drm_client_modeset.c:1182
 pan_display_atomic drivers/gpu/drm/drm_fb_helper.c:1387 [inline]
 drm_fb_helper_pan_display+0x3e8/0xc20 drivers/gpu/drm/drm_fb_helper.c:1447
 fb_pan_display+0x3a3/0x680 drivers/video/fbdev/core/fbmem.c:191
 bit_update_start+0x4d/0x1c0 drivers/video/fbdev/core/bitblit.c:380
 fbcon_switch+0x144d/0x2260 drivers/video/fbdev/core/fbcon.c:2187
 redraw_screen+0x55a/0xed0 drivers/tty/vt/vt.c:957
 con2fb_init_display drivers/video/fbdev/core/fbcon.c:811 [inline]
 set_con2fb_map+0xb3a/0x11e0 drivers/video/fbdev/core/fbcon.c:884
 do_fb_registered drivers/video/fbdev/core/fbcon.c:2993 [inline]
 fbcon_fb_registered+0x251/0x620 drivers/video/fbdev/core/fbcon.c:3009
 do_register_framebuffer drivers/video/fbdev/core/fbmem.c:449 [inline]
 register_framebuffer+0x65f/0x820 drivers/video/fbdev/core/fbmem.c:515
 __drm_fb_helper_initial_config_and_unlock+0x1624/0x1cf0 drivers/gpu/drm/drm_fb_helper.c:1851
 drm_fbdev_client_hotplug+0x16e/0x230 drivers/gpu/drm/clients/drm_fbdev_client.c:52
 drm_client_register+0x17f/0x210 drivers/gpu/drm/drm_client.c:140
 drm_fbdev_client_setup+0x1a9/0x3f0 drivers/gpu/drm/clients/drm_fbdev_client.c:159
 drm_client_setup+0x60/0x120 drivers/gpu/drm/clients/drm_client_setup.c:39
 virtio_gpu_probe+0x22b/0x3c0 drivers/gpu/drm/virtio/virtgpu_drv.c:110
 virtio_dev_probe+0x931/0xc80 drivers/virtio/virtio.c:341
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2b9/0xad0 drivers/base/dd.c:658
 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800
 driver_probe_device+0x50/0x430 drivers/base/dd.c:830
 __driver_attach+0x45f/0x710 drivers/base/dd.c:1216
 bus_for_each_dev+0x23e/0x2b0 drivers/base/bus.c:370
 bus_add_driver+0x346/0x670 drivers/base/bus.c:678
 driver_register+0x23a/0x320 drivers/base/driver.c:249
 virtio_gpu_driver_init+0xdd/0x190 drivers/gpu/drm/virtio/virtgpu_drv.c:185
 do_one_initcall+0x24a/0x940 init/main.c:1257
 do_initcall_level+0x157/0x210 init/main.c:1319
 do_initcalls+0x71/0xd0 init/main.c:1335
 kernel_init_freeable+0x432/0x5d0 init/main.c:1567
 kernel_init+0x1d/0x2b0 init/main.c:1457
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task kworker/0:1:10 blocked for more than 143 seconds.
      Not tainted 6.15.0-rc2-syzkaller-00278-gfc96b232f8e7 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1     state:D stack:25200 pid:10    tgid:10    ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: events virtio_gpu_dequeue_ctrl_func
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x1b88/0x5240 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x163/0x360 kernel/sched/core.c:6860
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
 __mutex_lock_common kernel/locking/mutex.c:678 [inline]
 __mutex_lock+0x805/0x10c0 kernel/locking/mutex.c:746
 drm_client_dev_hotplug+0xd0/0x4c0 drivers/gpu/drm/drm_client_event.c:96
 virtio_gpu_dequeue_ctrl_func+0x607/0xa50 drivers/gpu/drm/virtio/virtgpu_vq.c:263
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd50 kernel/workqueue.c:3400
 kthread+0x7b7/0x940 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task kworker/0:2:57 blocked for more than 143 seconds.
      Not tainted 6.15.0-rc2-syzkaller-00278-gfc96b232f8e7 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2     state:D stack:25688 pid:57    tgid:57    ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: events drm_fb_helper_damage_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x1b88/0x5240 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x163/0x360 kernel/sched/core.c:6860
 virtio_gpu_queue_ctrl_sgs drivers/gpu/drm/virtio/virtgpu_vq.c:397 [inline]
 virtio_gpu_queue_fenced_ctrl_buffer+0x750/0x1030 drivers/gpu/drm/virtio/virtgpu_vq.c:497
 virtio_gpu_resource_flush drivers/gpu/drm/virtio/virtgpu_plane.c:225 [inline]
 virtio_gpu_primary_plane_update+0xc8f/0x14a0 drivers/gpu/drm/virtio/virtgpu_plane.c:300
 drm_atomic_helper_commit_planes+0x5fb/0xe10 drivers/gpu/drm/drm_atomic_helper.c:2838
 drm_atomic_helper_commit_tail+0x5e/0x510 drivers/gpu/drm/drm_atomic_helper.c:1788
 commit_tail+0x2c4/0x3d0 drivers/gpu/drm/drm_atomic_helper.c:1873
 drm_atomic_helper_commit+0x95d/0xa00 drivers/gpu/drm/drm_atomic_helper.c:2111
 drm_atomic_commit+0x296/0x2f0 drivers/gpu/drm/drm_atomic.c:1518
 drm_atomic_helper_dirtyfb+0xd34/0xe90 drivers/gpu/drm/drm_damage_helper.c:181
 drm_fbdev_shmem_helper_fb_dirty+0x151/0x2e0 drivers/gpu/drm/drm_fbdev_shmem.c:117
 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:379 [inline]
 drm_fb_helper_damage_work+0x26c/0x910 drivers/gpu/drm/drm_fb_helper.c:402
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd50 kernel/workqueue.c:3400
 kthread+0x7b7/0x940 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Showing all locks held in the system:
9 locks held by swapper/0/1:
 #0: ffff8880008c3170 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
 #0: ffff8880008c3170 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
 #0: ffff8880008c3170 (&dev->mutex){....}-{4:4}, at: __driver_attach+0x454/0x710 drivers/base/dd.c:1215
 #1: ffff8880346362f8 (&dev->clientlist_mutex){+.+.}-{4:4}, at: drm_client_register+0x4e/0x210 drivers/gpu/drm/drm_client.c:126
 #2: ffffffff8f50c0c8 (registration_lock){+.+.}-{4:4}, at: register_framebuffer+0x8b/0x820 drivers/video/fbdev/core/fbmem.c:514
 #3: ffffffff8ec19a80 (console_lock){+.+.}-{0:0}, at: fbcon_fb_registered+0x54/0x620 drivers/video/fbdev/core/fbcon.c:3005
 #4: ffff88801d0bd280 (&helper->lock){+.+.}-{4:4}, at: drm_fb_helper_pan_display+0xbc/0xc20 drivers/gpu/drm/drm_fb_helper.c:1440
 #5: ffff8880346361b0 (&dev->master_mutex){+.+.}-{4:4}, at: drm_master_internal_acquire+0x20/0x70 drivers/gpu/drm/drm_auth.c:452
 #6: ffff88801d0bd098 (&client->modeset_mutex){+.+.}-{4:4}, at: drm_client_modeset_commit_locked+0x50/0x520 drivers/gpu/drm/drm_client_modeset.c:1180
 #7: ffffc90000136bf0 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_client_modeset_commit_atomic+0xd1/0x7d0 drivers/gpu/drm/drm_client_modeset.c:1018
 #8: ffffc90000136c18 (crtc_ww_class_mutex){+.+.}-{4:4}, at: drm_client_modeset_commit_atomic+0xd1/0x7d0 drivers/gpu/drm/drm_client_modeset.c:1018
3 locks held by kworker/0:1/10:
 #0: ffff88801b074d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801b074d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
 #1: ffffc900001c7c60 ((work_completion)(&vgvq->dequeue_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc900001c7c60 ((work_completion)(&vgvq->dequeue_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
 #2: ffff8880346362f8 (&dev->clientlist_mutex){+.+.}-{4:4}, at: drm_client_dev_hotplug+0xd0/0x4c0 drivers/gpu/drm/drm_client_event.c:96
1 lock held by khungtaskd/26:
 #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764
2 locks held by kworker/u4:3/47:
 #0: ffff88801b079148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801b079148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
 #1: ffffc9000062fc60 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000062fc60 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
5 locks held by kworker/0:2/57:
 #0: ffff88801b074d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801b074d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
 #1: ffffc9000104fc60 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000104fc60 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
 #2: ffffc9000104f8b0 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_atomic_helper_dirtyfb+0xcb/0xe90 drivers/gpu/drm/drm_damage_helper.c:123
 #3: ffffc9000104f8d8 (crtc_ww_class_mutex){+.+.}-{4:4}, at: drm_atomic_helper_dirtyfb+0xcb/0xe90 drivers/gpu/drm/drm_damage_helper.c:123
 #4: ffffffff8f5e5d90 (drm_unplug_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
 #4: ffffffff8f5e5d90 (drm_unplug_srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
 #4: ffffffff8f5e5d90 (drm_unplug_srcu){.+.+}-{0:0}, at: drm_dev_enter+0x48/0x160 drivers/gpu/drm/drm_drv.c:451

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