syzbot

INFO: task swapper/0:1 blocked for more than 143 seconds.
      Not tainted 6.12.0-rc6-syzkaller-00005-g557329bcecc2 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:swapper/0       state:D stack:18288 pid:1     tgid:1     ppid:0      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x184f/0x4c30 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6782
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6839
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __ww_mutex_lock+0xec5/0x2790 kernel/locking/mutex.c:759
 ww_mutex_lock+0x40/0x1f0 kernel/locking/mutex.c:876
 modeset_lock+0x2bf/0x650 drivers/gpu/drm/drm_modeset_lock.c:314
 drm_atomic_get_plane_state+0x1c1/0x500 drivers/gpu/drm/drm_atomic.c:541
 drm_client_modeset_commit_atomic+0x1a1/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1020
 drm_client_modeset_commit_locked+0xe0/0x520 drivers/gpu/drm/drm_client_modeset.c:1171
 pan_display_atomic drivers/gpu/drm/drm_fb_helper.c:1371 [inline]
 drm_fb_helper_pan_display+0x379/0xc10 drivers/gpu/drm/drm_fb_helper.c:1431
 fb_pan_display+0x3a3/0x680 drivers/video/fbdev/core/fbmem.c:191
 bit_update_start+0x4d/0x1c0 drivers/video/fbdev/core/bitblit.c:381
 fbcon_switch+0x144b/0x2250 drivers/video/fbdev/core/fbcon.c:2186
 redraw_screen+0x546/0xe90 drivers/tty/vt/vt.c:957
 con2fb_init_display drivers/video/fbdev/core/fbcon.c:824 [inline]
 set_con2fb_map+0xc96/0x11e0 drivers/video/fbdev/core/fbcon.c:885
 do_fb_registered drivers/video/fbdev/core/fbcon.c:2992 [inline]
 fbcon_fb_registered+0x251/0x620 drivers/video/fbdev/core/fbcon.c:3008
 do_register_framebuffer drivers/video/fbdev/core/fbmem.c:449 [inline]
 register_framebuffer+0x654/0x810 drivers/video/fbdev/core/fbmem.c:515
 __drm_fb_helper_initial_config_and_unlock+0x1716/0x1df0 drivers/gpu/drm/drm_fb_helper.c:1869
 drm_fbdev_shmem_client_hotplug+0x16e/0x230 drivers/gpu/drm/drm_fbdev_shmem.c:250
 drm_client_register+0x17f/0x210 drivers/gpu/drm/drm_client.c:141
 virtio_gpu_probe+0x22e/0x3c0 drivers/gpu/drm/virtio/virtgpu_drv.c:106
 virtio_dev_probe+0x931/0xc80 drivers/virtio/virtio.c:341
 really_probe+0x2b8/0xad0 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+0x239/0x2b0 drivers/base/bus.c:370
 bus_add_driver+0x346/0x670 drivers/base/bus.c:675
 driver_register+0x23a/0x320 drivers/base/driver.c:246
 do_one_initcall+0x248/0x880 init/main.c:1269
 do_initcall_level+0x157/0x210 init/main.c:1331
 do_initcalls+0x3f/0x80 init/main.c:1347
 kernel_init_freeable+0x435/0x5d0 init/main.c:1580
 kernel_init+0x1d/0x2b0 init/main.c:1469
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task kworker/0:1:9 blocked for more than 143 seconds.
      Not tainted 6.12.0-rc6-syzkaller-00005-g557329bcecc2 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1     state:D stack:24528 pid:9     tgid:9     ppid:2      flags:0x00004000
Workqueue: events virtio_gpu_dequeue_ctrl_func
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x184f/0x4c30 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6782
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6839
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
 drm_client_dev_hotplug+0xd0/0x3c0 drivers/gpu/drm/drm_client.c:230
 virtio_gpu_dequeue_ctrl_func+0x605/0xa50 drivers/gpu/drm/virtio/virtgpu_vq.c:235
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task kworker/0:2:784 blocked for more than 143 seconds.
      Not tainted 6.12.0-rc6-syzkaller-00005-g557329bcecc2 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2     state:D stack:24560 pid:784   tgid:784   ppid:2      flags:0x00004000
Workqueue: events drm_fb_helper_damage_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x184f/0x4c30 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6782
 virtio_gpu_queue_ctrl_sgs drivers/gpu/drm/virtio/virtgpu_vq.c:341 [inline]
 virtio_gpu_queue_fenced_ctrl_buffer+0x720/0xff0 drivers/gpu/drm/virtio/virtgpu_vq.c:415
 virtio_gpu_resource_flush drivers/gpu/drm/virtio/virtgpu_plane.c:162 [inline]
 virtio_gpu_primary_plane_update+0xd39/0x1590 drivers/gpu/drm/virtio/virtgpu_plane.c:237
 drm_atomic_helper_commit_planes+0x5ee/0xe00 drivers/gpu/drm/drm_atomic_helper.c:2800
 drm_atomic_helper_commit_tail+0x5e/0x500 drivers/gpu/drm/drm_atomic_helper.c:1750
 commit_tail+0x2c1/0x3c0 drivers/gpu/drm/drm_atomic_helper.c:1835
 drm_atomic_helper_commit+0x953/0x9f0 drivers/gpu/drm/drm_atomic_helper.c:2073
 drm_atomic_commit+0x296/0x2f0 drivers/gpu/drm/drm_atomic.c:1516
 drm_atomic_helper_dirtyfb+0xd10/0xe70 drivers/gpu/drm/drm_damage_helper.c:181
 drm_fbdev_shmem_helper_fb_dirty+0x151/0x2c0 drivers/gpu/drm/drm_fbdev_shmem.c:197
 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:376 [inline]
 drm_fb_helper_damage_work+0x275/0x880 drivers/gpu/drm/drm_fb_helper.c:399
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Showing all locks held in the system:
9 locks held by swapper/0/1:
 #0: ffff8880339e6170 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
 #0: ffff8880339e6170 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
 #0: ffff8880339e6170 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x454/0x710 drivers/base/dd.c:1215
 #1: ffff88801f7402f8 (&dev->clientlist_mutex){+.+.}-{3:3}, at: drm_client_register+0x4e/0x210 drivers/gpu/drm/drm_client.c:127
 #2: ffffffff8f0ed0c8 (registration_lock){+.+.}-{3:3}, at: register_framebuffer+0x87/0x810 drivers/video/fbdev/core/fbmem.c:514
 #3: ffffffff8e813380 (console_lock){+.+.}-{0:0}, at: fbcon_fb_registered+0x54/0x620 drivers/video/fbdev/core/fbcon.c:3004
 #4: ffff888033f4da80 (&helper->lock){+.+.}-{3:3}, at: drm_fb_helper_pan_display+0xbc/0xc10 drivers/gpu/drm/drm_fb_helper.c:1424
 #5: ffff88801f7401b0 (&dev->master_mutex){+.+.}-{3:3}, at: drm_master_internal_acquire+0x20/0x70 drivers/gpu/drm/drm_auth.c:452
 #6: ffff888033f4d898 (&client->modeset_mutex){+.+.}-{3:3}, at: drm_client_modeset_commit_locked+0x50/0x520 drivers/gpu/drm/drm_client_modeset.c:1169
 #7: ffffc90000336cd0 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_client_modeset_commit_atomic+0xd5/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1007
 #8: ffff888033f610b0 (crtc_ww_class_mutex){+.+.}-{3:3}, at: modeset_lock+0x2bf/0x650 drivers/gpu/drm/drm_modeset_lock.c:314
3 locks held by kworker/0:1/9:
 #0: ffff88801ac74948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff88801ac74948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
 #1: ffffc900003b7d00 ((work_completion)(&vgvq->dequeue_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc900003b7d00 ((work_completion)(&vgvq->dequeue_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
 #2: ffff88801f7402f8 (&dev->clientlist_mutex){+.+.}-{3:3}, at: drm_client_dev_hotplug+0xd0/0x3c0 drivers/gpu/drm/drm_client.c:230
1 lock held by khungtaskd/25:
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720
2 locks held by kworker/u4:3/46:
 #0: ffff88801ac79148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff88801ac79148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
 #1: ffffc9000060fd00 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc9000060fd00 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
5 locks held by kworker/0:2/784:
 #0: ffff88801ac74948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff88801ac74948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
 #1: ffffc90001827d00 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc90001827d00 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
 #2: ffffc90001827970 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_atomic_helper_dirtyfb+0xce/0xe70 drivers/gpu/drm/drm_damage_helper.c:123
 #3: ffff888033f610b0 (crtc_ww_class_mutex){+.+.}-{3:3}, at: modeset_lock+0x2bf/0x650 drivers/gpu/drm/drm_modeset_lock.c:314
 #4: ffffffff8f1c75f0 (drm_unplug_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:151 [inline]
 #4: ffffffff8f1c75f0 (drm_unplug_srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:250 [inline]
 #4: ffffffff8f1c75f0 (drm_unplug_srcu){.+.+}-{0:0}, at: drm_dev_enter+0x45/0x150 drivers/gpu/drm/drm_drv.c:448

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