------------[ cut here ]------------
[CRTC:37:crtc-0] vblank wait timed out
WARNING: drivers/gpu/drm/drm_atomic_helper.c:1922 at drm_atomic_helper_wait_for_vblanks+0x790/0x900, CPU#0: syz.4.3097/13241
Modules linked in:
CPU: 0 UID: 0 PID: 13241 Comm: syz.4.3097 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:drm_atomic_helper_wait_for_vblanks+0x7c9/0x900
Code: 8d 00 00 00 49 83 c5 20 45 8b 3f 4c 89 e8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ef e8 f1 91 c6 fc 49 8b 55 00 4c 89 f7 44 89 fe <67> 48 0f b9 3a 4d 89 e5 e9 3f ff ff ff 44 89 f1 80 e1 07 80 c1 03
RSP: 0018:ffffc90020736d20 EFLAGS: 00010246
RAX: 1ffff110207efa9d RBX: dffffc0000000000 RCX: 0000000000080000
RDX: ffff88816b01d040 RSI: 0000000000000025 RDI: ffffffff8f961d70
RBP: ffffc90020736e48 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f1597f R12: ffff88810a5fcc28
R13: ffff888103f7d4e8 R14: ffffffff8f961d70 R15: 0000000000000025
FS:  00007fad83bed6c0(0000) GS:ffff88818e91f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055557b5bd4e8 CR3: 0000000113cee000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 drm_atomic_helper_commit_tail+0x2c3/0x4f0
 commit_tail+0x29a/0x3a0
 drm_atomic_helper_commit+0xa6e/0xb10
 drm_atomic_commit+0x246/0x2b0
 drm_client_modeset_commit_atomic+0x660/0x7e0
 drm_client_modeset_commit_locked+0xce/0x4d0
 drm_fb_helper_pan_display+0x3ea/0xbe0
 fb_pan_display+0x39e/0x680
 bit_update_start+0x4c/0x1e0
 fbcon_switch+0x127e/0x2040
 csi_J+0x6c4/0xe50
 do_con_write+0x45d9/0x5930
 con_write+0x31/0x2e0
 n_tty_write+0xd55/0x1220
 file_tty_write+0x561/0xa10
 vfs_write+0x629/0xba0
 ksys_write+0x156/0x270
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fad859bcdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fad83bed028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fad85c36090 RCX: 00007fad859bcdd9
RDX: 0000000000001006 RSI: 0000200000002080 RDI: 0000000000000006
RBP: 00007fad85a52d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fad85c36128 R14: 00007fad85c36090 R15: 00007ffcc88d6a08
 </TASK>
