syzbot


WARNING in drm_wait_one_vblank

Status: upstream: reported on 2026/04/04 20:24
Reported-by: syzbot+5dd5021268907ad234d0@syzkaller.appspotmail.com
First crash: 2d17h, last: 2d17h
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in drm_wait_one_vblank dri -1 C error inconclusive 375 795d 1798d 0/29 auto-obsoleted due to no activity on 2024/04/11 15:51
linux-5.15 WARNING in drm_wait_one_vblank missing-backport origin:upstream -1 C inconclusive 24 6d02h 1103d 0/3 upstream: reported C repro on 2023/03/31 07:06
upstream WARNING in drm_wait_one_vblank (2) dri -1 C error 3650 90d 614d 29/29 fixed on 2026/01/07 12:29
linux-6.1 WARNING in drm_wait_one_vblank origin:upstream missing-backport -1 C inconclusive 9 163d 1098d 0/3 upstream: reported C repro on 2023/04/05 12:39
upstream WARNING in drm_wait_one_vblank (3) dri -1 C error error 3128 23d 86d 0/29 upstream: reported C repro on 2026/01/11 12:41

Sample crash report:
platform vkms: vblank wait timed out on crtc 0
WARNING: CPU: 0 PID: 14044 at drivers/gpu/drm/drm_vblank.c:1310 drm_wait_one_vblank+0x934/0x9b0 drivers/gpu/drm/drm_vblank.c:-1
Modules linked in:
CPU: 0 PID: 14044 Comm: syz.9.1509 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:drm_wait_one_vblank+0x934/0x9b0 drivers/gpu/drm/drm_vblank.c:1310
Code: df 80 3c 08 00 74 08 48 89 df e8 e7 ce 17 fd 4c 8b 3b 48 c7 c7 a0 23 2f 8b 4c 89 f6 4c 89 fa 44 89 e1 e8 ef 4a 89 fc 44 89 e6 <0f> 0b 49 bf 00 00 00 00 00 fc ff df e9 ac fb ff ff 89 d9 80 e1 07
RSP: 0018:ffffc900046efac0 EFLAGS: 00010246
RAX: a613a1c4414b7900 RBX: ffff888146ef2010 RCX: 0000000000080000
RDX: ffffc90004c11000 RSI: 0000000000000000 RDI: 000000000002c035
RBP: ffffc900046efc00 R08: ffffc900046ef6c7 R09: 1ffff920008dded8
R10: dffffc0000000000 R11: fffff520008dded9 R12: 0000000000000000
R13: 1ffff920008ddf64 R14: ffffffff8b418540 R15: ffff88823bcbcff8
FS:  00007fafe7d706c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fafe6fe9f00 CR3: 000000007d76e000 CR4: 00000000003506f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 drm_fb_helper_ioctl+0x116/0x140 drivers/gpu/drm/drm_fb_helper.c:1106
 do_fb_ioctl+0x4c7/0x7f0 drivers/video/fbdev/core/fb_chrdev.c:155
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fafe6f9c819
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:00007fafe7d70028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fafe7215fa0 RCX: 00007fafe6f9c819
RDX: 0000000000000000 RSI: 0000000040044620 RDI: 0000000000000004
RBP: 00007fafe7032c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fafe7216038 R14: 00007fafe7215fa0 R15: 00007fff901a8e18
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/04 20:23 linux-6.6.y c09fbcd31ae6 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in drm_wait_one_vblank
* Struck through repros no longer work on HEAD.