syzbot

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WARNING: CPU: 3 PID: 34 at drivers/gpu/drm/virtio/virtgpu_vq.c:414 virtio_gpu_queue_ctrl_sgs drivers/gpu/drm/virtio/virtgpu_vq.c:414 [inline]
WARNING: CPU: 3 PID: 34 at drivers/gpu/drm/virtio/virtgpu_vq.c:414 virtio_gpu_queue_fenced_ctrl_buffer+0xbcf/0xfc0 drivers/gpu/drm/virtio/virtgpu_vq.c:497
Modules linked in:
CPU: 3 UID: 0 PID: 34 Comm: kworker/3:0 Not tainted 6.15.0-rc1-syzkaller-00325-g7cdabafc0012 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events drm_fb_helper_damage_work
RIP: 0010:virtio_gpu_queue_ctrl_sgs drivers/gpu/drm/virtio/virtgpu_vq.c:414 [inline]
RIP: 0010:virtio_gpu_queue_fenced_ctrl_buffer+0xbcf/0xfc0 drivers/gpu/drm/virtio/virtgpu_vq.c:497
Code: df e8 a5 45 d5 fe 48 89 9c 24 a8 01 00 00 c7 44 24 30 02 00 00 00 48 c7 44 24 18 00 00 00 00 e9 4f f6 ff ff e8 f2 97 c3 fb 90 <0f> 0b 90 e9 02 fa ff ff e8 e4 97 c3 fb 90 0f 0b e8 dc 97 c3 fb 90
RSP: 0018:ffffc900006df488 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 00000000fffffffb RCX: ffffffff85f79f81
RDX: ffff88801e2d4880 RSI: ffffffff85f7a57e RDI: 0000000000000005
RBP: ffff888104ea7c00 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000fffffffb R11: 0000000000000000 R12: ffffed10209d4f85
R13: ffff8880245976f8 R14: ffff888025553ac8 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880d6cb2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa4a49be440 CR3: 000000000e182000 CR4: 0000000000352ef0
DR0: 00000000000007ff DR1: 0000000000000009 DR2: 0002000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 virtio_gpu_update_dumb_bo drivers/gpu/drm/virtio/virtgpu_plane.c:175 [inline]
 virtio_gpu_primary_plane_update+0xda0/0x1540 drivers/gpu/drm/virtio/virtgpu_plane.c:264
 drm_atomic_helper_commit_planes+0x954/0x1010 drivers/gpu/drm/drm_atomic_helper.c:2838
 drm_atomic_helper_commit_tail+0x69/0xf0 drivers/gpu/drm/drm_atomic_helper.c:1788
 commit_tail+0x35b/0x400 drivers/gpu/drm/drm_atomic_helper.c:1873
 drm_atomic_helper_commit+0x2fd/0x380 drivers/gpu/drm/drm_atomic_helper.c:2111
 drm_atomic_commit+0x231/0x300 drivers/gpu/drm/drm_atomic.c:1518
 drm_atomic_helper_dirtyfb+0x5fd/0x780 drivers/gpu/drm/drm_damage_helper.c:181
 drm_fbdev_shmem_helper_fb_dirty+0x1c9/0x340 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+0x27b/0x5f0 drivers/gpu/drm/drm_fb_helper.c:402
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>