Good day, dear maintainers, We found a bug using a modified version of syzkaller.
Kernel Branch: 7.0-rc1 Kernel Config: <https://drive.google.com/open?id=173DLEAEPKPhhR1TcqofdnkLpdoK7PMFl> Unfortunately, we don't have any reproducer for this bug yet. Thank you! Best regards, Sanan Hasanov ------------[ cut here ]------------ [CRTC:35:crtc-0] vblank wait timed out WARNING: at drm_atomic_helper_wait_for_vblanks+0x764/0x8f0 drivers/gpu/drm/drm_atomic_helper.c:1921, CPU#1: kworker/1:1/30 Modules linked in: CPU: 1 UID: 0 PID: 30 Comm: kworker/1:1 Not tainted 7.0.0-rc1 #1 PREEMPT(full) Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: events drm_fb_helper_damage_work RIP: 0010:drm_atomic_helper_wait_for_vblanks+0x7b0/0x8f0 drivers/gpu/drm/drm_atomic_helper.c:1921 Code: 45 8b b6 88 00 00 00 4c 8d 68 20 4c 89 e8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ef e8 9a 83 f4 fc 49 8b 55 00 4c 89 ff 44 89 f6 <67> 48 0f b9 3a 4d 89 e5 e9 34 ff ff ff 44 89 f1 80 e1 07 80 c1 03 RSP: 0018:ffffc900002075a0 EFLAGS: 00010246 RAX: 1ffff11003a891c3 RBX: dffffc0000000000 RCX: ffff88801330e180 RDX: ffff88801c9712c0 RSI: 0000000000000023 RDI: ffffffff906b49a8 RBP: ffffc900002076e0 R08: ffff88801d478833 R09: 1ffff11003a8f106 R10: dffffc0000000000 R11: ffffed1003a8f107 R12: ffff88801ca0ec28 R13: ffff88801d448e18 R14: 0000000000000023 R15: ffffffff906b49a8 FS: 0000000000000000(0000) GS:ffff8880d99df000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000000e6ff000 CR4: 00000000000006f0 Call Trace: <TASK> drm_atomic_helper_commit_tail+0x2d2/0x4e0 drivers/gpu/drm/drm_atomic_helper.c:1997 commit_tail+0x298/0x3a0 drivers/gpu/drm/drm_atomic_helper.c:2074 drm_atomic_helper_commit+0xa2e/0xad0 drivers/gpu/drm/drm_atomic_helper.c:2312 drm_atomic_commit+0x261/0x2c0 drivers/gpu/drm/drm_atomic.c:1775 drm_atomic_helper_dirtyfb+0xdc0/0xf10 drivers/gpu/drm/drm_damage_helper.c:183 drm_fbdev_shmem_helper_fb_dirty+0x161/0x2d0 drivers/gpu/drm/drm_fbdev_shmem.c:117 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:248 [inline] drm_fb_helper_damage_work+0x296/0x720 drivers/gpu/drm/drm_fb_helper.c:274 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0x811/0xf10 kernel/workqueue.c:3358 worker_thread+0x9c1/0xeb0 kernel/workqueue.c:3439 kthread+0x3c1/0x4d0 kernel/kthread.c:467 ret_from_fork+0x608/0xc40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:245 </TASK> ---------------- Code disassembly (best guess): 0: 45 8b b6 88 00 00 00 mov 0x88(%r14),%r14d 7: 4c 8d 68 20 lea 0x20(%rax),%r13 b: 4c 89 e8 mov %r13,%rax e: 48 c1 e8 03 shr $0x3,%rax 12: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1) 16: 74 08 je 0x20 18: 4c 89 ef mov %r13,%rdi 1b: e8 9a 83 f4 fc call 0xfcf483ba 20: 49 8b 55 00 mov 0x0(%r13),%rdx 24: 4c 89 ff mov %r15,%rdi 27: 44 89 f6 mov %r14d,%esi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 4d 89 e5 mov %r12,%r13 32: e9 34 ff ff ff jmp 0xffffff6b 37: 44 89 f1 mov %r14d,%ecx 3a: 80 e1 07 and $0x7,%cl 3d: 80 c1 03 add $0x3,%cl <<<<<<<<<<<<<<< tail report >>>>>>>>>>>>>>>
