Hello, syzbot found the following issue on: HEAD commit: 3efc57369a0c Merge tag 'for-linus' of git://git.kernel.org.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=12964d9f980000 kernel config: https://syzkaller.appspot.com/x/.config?x=a4fcb065287cdb84 dashboard link: https://syzkaller.appspot.com/bug?extid=eee643fdccb7c015b3a6 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-3efc5736.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/d0988c372a39/vmlinux-3efc5736.xz kernel image: https://storage.googleapis.com/syzbot-assets/8547f30d7e9d/bzImage-3efc5736.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+eee643fdccb7c015b3a6@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task swapper/0:1 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-11993-g3efc57369a0c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:swapper/0 state:D stack:17904 pid:1 tgid:1 ppid:0 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 __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 fbcon_prepare_logo+0x9ba/0xd20 drivers/video/fbdev/core/fbcon.c:633 con2fb_init_display drivers/video/fbdev/core/fbcon.c:819 [inline] set_con2fb_map+0xc24/0x11e0 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 6.11.0-syzkaller-11993-g3efc57369a0c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:1 state:D stack:26192 pid:9 tgid:9 ppid:2 flags:0x00004000 Workqueue: events virtio_gpu_dequeue_ctrl_func Call Trace: <TASK> context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 __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/0:2:783 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-11993-g3efc57369a0c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:2 state:D stack:24368 pid:783 tgid:783 ppid:2 flags:0x00004000 Workqueue: events drm_fb_helper_damage_work Call Trace: <TASK> context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 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: ffff88801fb62170 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #0: ffff88801fb62170 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #0: ffff88801fb62170 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x454/0x710 drivers/base/dd.c:1215 #1: ffff8880331942f8 (&dev->clientlist_mutex){+.+.}-{3:3}, at: drm_client_register+0x4e/0x210 drivers/gpu/drm/drm_client.c:127 #2: ffffffff8f0eb208 (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: ffff8880004cf280 (&helper->lock){+.+.}-{3:3}, at: drm_fb_helper_pan_display+0xbc/0xc10 drivers/gpu/drm/drm_fb_helper.c:1424 #5: ffff8880331941b0 (&dev->master_mutex){+.+.}-{3:3}, at: drm_master_internal_acquire+0x20/0x70 drivers/gpu/drm/drm_auth.c:452 #6: ffff8880004cf098 (&client->modeset_mutex){+.+.}-{3:3}, at: drm_client_modeset_commit_locked+0x50/0x520 drivers/gpu/drm/drm_client_modeset.c:1169 #7: ffffc90000336bf0 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_client_modeset_commit_atomic+0xd5/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1007 #8: ffff8880004d20b0 (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: ffff8880331942f8 (&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:6701 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 2 locks held by kswapd0/75: 5 locks held by kworker/0:2/783: #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: ffffc9000179fd00 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000179fd00 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffc9000179f970 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_atomic_helper_dirtyfb+0xce/0xe70 drivers/gpu/drm/drm_damage_helper.c:123 #3: ffff8880004d20b0 (crtc_ww_class_mutex){+.+.}-{3:3}, at: modeset_lock+0x2bf/0x650 drivers/gpu/drm/drm_modeset_lock.c:314 #4: ffffffff8f1c5730 (drm_unplug_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:151 [inline] #4: ffffffff8f1c5730 (drm_unplug_srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:250 [inline] #4: ffffffff8f1c5730 (drm_unplug_srcu){.+.+}-{0:0}, at: drm_dev_enter+0x45/0x150 drivers/gpu/drm/drm_drv.c:448 ============================================= --- This report is generated by a bot. 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