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WARNING in drm_atomic_helper_wait_for_vblanks (6)

Status: upstream: reported on 2026/05/27 22:06
Subsystems: dri
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+45bc7264de77caad91cb@syzkaller.appspotmail.com
First crash: 50d, last: 9d15h
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
936efca7-6ce8-48b7-a649-a83dcacb6798 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in drm_atomic_helper_wait_for_vblanks (6) 2026/06/02 09:03 2026/06/02 09:03 2026/06/02 09:58 1095583bae1d2729a3b4be301cb6ddc85ced9e38

			
		
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [dri?] WARNING in drm_atomic_helper_wait_for_vblanks (6) 0 (1) 2026/05/27 22:06
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in drm_atomic_helper_wait_for_vblanks (5) dri -1 syz 464 63d 216d 29/29 fixed on 2026/05/21 07:49
upstream WARNING in drm_atomic_helper_wait_for_vblanks (3) dri -1 14 724d 778d 0/29 auto-obsoleted due to no activity on 2024/09/27 07:41
upstream WARNING in drm_atomic_helper_wait_for_vblanks (2) dri -1 1 1525d 1521d 0/29 auto-obsoleted due to no activity on 2022/09/07 08:02
upstream WARNING in drm_atomic_helper_wait_for_vblanks (4) dri -1 2 382d 407d 0/29 auto-obsoleted due to no activity on 2025/10/04 15:38
upstream WARNING in drm_atomic_helper_wait_for_vblanks dri -1 1 1654d 1650d 0/29 auto-closed as invalid on 2022/05/01 08:40

Sample crash report:
------------[ cut here ]------------
[CRTC:39:crtc-0] vblank wait timed out
WARNING: drivers/gpu/drm/drm_atomic_helper.c:1921 at drm_atomic_helper_wait_for_vblanks.part.0+0x738/0x8a0 drivers/gpu/drm/drm_atomic_helper.c:1921, CPU#2: syz.7.2609/15359
Modules linked in:
CPU: 2 UID: 0 PID: 15359 Comm: syz.7.2609 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:drm_atomic_helper_wait_for_vblanks.part.0+0x73e/0x8a0 drivers/gpu/drm/drm_atomic_helper.c:1921
Code: 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 0f b6 04 01 84 c0 74 08 3c 03 0f 8e 44 01 00 00 48 8d 3d 98 61 61 0b 8b b3 d0 00 00 00 <67> 48 0f b9 3a e9 e1 fc ff ff e8 c3 67 3d fc e9 7c fe ff ff e8 a9
RSP: 0018:ffffc900042277b8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888101a80040 RCX: 1ffff11020350022
RDX: ffff888027680d80 RSI: 0000000000000027 RDI: ffffffff912dca60
RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88806280a900
FS:  00007f2da2c026c0(0000) GS:ffff8880d5fee000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc4e394f58 CR3: 000000002d676000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000001800
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 drm_atomic_helper_wait_for_vblanks drivers/gpu/drm/drm_atomic_helper.c:1895 [inline]
 drm_atomic_helper_commit_tail+0xff/0x130 drivers/gpu/drm/drm_atomic_helper.c:1997
 commit_tail+0x338/0x430 drivers/gpu/drm/drm_atomic_helper.c:2074
 drm_atomic_helper_commit+0x303/0x380 drivers/gpu/drm/drm_atomic_helper.c:2312
 drm_atomic_commit+0x230/0x300 drivers/gpu/drm/drm_atomic.c:1789
 drm_atomic_helper_dirtyfb+0x603/0x790 drivers/gpu/drm/drm_damage_helper.c:183
 drm_mode_dirtyfb_ioctl+0x31d/0x460 drivers/gpu/drm/drm_framebuffer.c:765
 drm_ioctl_kernel+0x1f3/0x3e0 drivers/gpu/drm/drm_ioctl.c:805
 drm_ioctl+0x5e6/0xc60 drivers/gpu/drm/drm_ioctl.c:902
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2da1d9de59
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:00007f2da2c02028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f2da2025fa0 RCX: 00007f2da1d9de59
RDX: 0000200000000080 RSI: 00000000c01864b1 RDI: 000000000000000c
RBP: 00007f2da1e33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2da2026038 R14: 00007f2da2025fa0 R15: 00007ffc4e395bb8
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 fc                	add    %bh,%ah
   4:	ff                   	lcall  (bad)
   5:	df 48 89             	fisttps -0x77(%rax)
   8:	f9                   	stc
   9:	48 c1 e9 03          	shr    $0x3,%rcx
   d:	0f b6 04 01          	movzbl (%rcx,%rax,1),%eax
  11:	84 c0                	test   %al,%al
  13:	74 08                	je     0x1d
  15:	3c 03                	cmp    $0x3,%al
  17:	0f 8e 44 01 00 00    	jle    0x161
  1d:	48 8d 3d 98 61 61 0b 	lea    0xb616198(%rip),%rdi        # 0xb6161bc
  24:	8b b3 d0 00 00 00    	mov    0xd0(%rbx),%esi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	e9 e1 fc ff ff       	jmp    0xfffffd15
  34:	e8 c3 67 3d fc       	call   0xfc3d67fc
  39:	e9 7c fe ff ff       	jmp    0xfffffeba
  3e:	e8                   	.byte 0xe8
  3f:	a9                   	.byte 0xa9

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/04 00:23 upstream d2c9a99135da aa437a8a .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in drm_atomic_helper_wait_for_vblanks
2026/07/01 17:25 upstream 665159e24674 5fb9973c .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in drm_atomic_helper_wait_for_vblanks
2026/06/30 03:30 upstream dc59e4fea9d8 fff8d0a0 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in drm_atomic_helper_wait_for_vblanks
2026/06/27 20:50 upstream 5a66900afbd6 fb92f11c .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in drm_atomic_helper_wait_for_vblanks
2026/06/26 20:11 upstream 51cb1aa1250c fb92f11c .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in drm_atomic_helper_wait_for_vblanks
2026/06/21 21:39 upstream 8cd8cf7a07e5 43bfcdb0 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in drm_atomic_helper_wait_for_vblanks
2026/06/19 06:24 upstream 9e7e66334583 d7ffd47b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in drm_atomic_helper_wait_for_vblanks
2026/05/23 21:56 upstream 79bd2dded182 c69befb3 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in drm_atomic_helper_wait_for_vblanks
* Struck through repros no longer work on HEAD.