syzbot


WARNING in vkms_get_vblank_timestamp

Status: upstream: reported C repro on 2024/10/05 17:59
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+54873342b67d3c8c4a38@syzkaller.appspotmail.com
First crash: 37d, last: 2d17h
Bug presence (1)
Date Name Commit Repro Result
2024/10/14 upstream (ToT) 6485cf5ea253 C [report] WARNING in vkms_get_vblank_timestamp
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in vkms_get_vblank_timestamp dri syz error 41 526d 585d 22/28 fixed on 2023/06/08 14:41
linux-6.1 WARNING in vkms_get_vblank_timestamp origin:upstream C error 2 58d 242d 0/3 upstream: reported C repro on 2024/03/14 22:37
upstream WARNING in vkms_get_vblank_timestamp (2) dri C done 315 1d15h 518d 0/28 upstream: reported C repro on 2023/06/13 03:40
Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/10/20 07:27 17m retest repro linux-5.15.y report log

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4036 at drivers/gpu/drm/vkms/vkms_crtc.c:103 vkms_get_vblank_timestamp+0x1a4/0x1d4 drivers/gpu/drm/vkms/vkms_crtc.c:103
Modules linked in:
CPU: 0 PID: 4036 Comm: syz-executor892 Not tainted 5.15.171-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
pstate: 804000c5 (Nzcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : vkms_get_vblank_timestamp+0x1a4/0x1d4 drivers/gpu/drm/vkms/vkms_crtc.c:103
lr : vkms_get_vblank_timestamp+0x1a4/0x1d4 drivers/gpu/drm/vkms/vkms_crtc.c:103
sp : ffff80001f9771b0
x29: ffff80001f9771b0 x28: ffff80001f977270 x27: ffff0000cb40cee8
x26: ffff80001f977260 x25: 1ffff00003f2ee4e x24: 0000000000000000
x23: ffff0000cb40c000 x22: dfff800000000000 x21: 0000000ad685d119
x20: 0000000ad685d119 x19: ffff80001f977270 x18: 0000000000000000
x17: 0000000000000000 x16: ffff8000083052d8 x15: 0000000000000008
x14: 1ffff0000295a06a x13: dfff800000000000 x12: ffff700003f2ee48
x11: 0000000000000003 x10: 0000000000000000 x9 : ffff0000cd09b680
x8 : ffff80000b80a6cc x7 : ffff80000b71c110 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : ffff80001f977270 x1 : 0000000ad685d119 x0 : 0000000ad685d119
Call trace:
 vkms_get_vblank_timestamp+0x1a4/0x1d4 drivers/gpu/drm/vkms/vkms_crtc.c:103
 drm_get_last_vbltimestamp drivers/gpu/drm/drm_vblank.c:881 [inline]
 drm_update_vblank_count+0x23c/0xb10 drivers/gpu/drm/drm_vblank.c:303
 drm_vblank_disable_and_save+0xc8/0x344 drivers/gpu/drm/drm_vblank.c:477
 drm_crtc_vblank_off+0x254/0x7c4 drivers/gpu/drm/drm_vblank.c:1325
 vkms_crtc_atomic_disable+0x20/0x30 drivers/gpu/drm/vkms/vkms_crtc.c:234
 disable_outputs drivers/gpu/drm/drm_atomic_helper.c:1117 [inline]
 drm_atomic_helper_commit_modeset_disables+0xa10/0x1488 drivers/gpu/drm/drm_atomic_helper.c:1321
 vkms_atomic_commit_tail+0x5c/0x20c drivers/gpu/drm/vkms/vkms_drv.c:71
 commit_tail+0x274/0x3cc drivers/gpu/drm/drm_atomic_helper.c:1693
 drm_atomic_helper_commit+0x5fc/0x644 drivers/gpu/drm/drm_atomic_helper.c:1912
 drm_atomic_commit+0xd8/0xf8 drivers/gpu/drm/drm_atomic.c:1426
 drm_client_modeset_commit_atomic+0x594/0x730 drivers/gpu/drm/drm_client_modeset.c:1055
 drm_client_modeset_commit_locked+0xd0/0x4a8 drivers/gpu/drm/drm_client_modeset.c:1158
 drm_client_modeset_commit+0x50/0x7c drivers/gpu/drm/drm_client_modeset.c:1184
 __drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:252 [inline]
 drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:279 [inline]
 drm_fb_helper_lastclose drivers/gpu/drm/drm_fb_helper.c:2005 [inline]
 drm_fbdev_client_restore+0xe8/0x17c drivers/gpu/drm/drm_fb_helper.c:2408
 drm_client_dev_restore+0x12c/0x248 drivers/gpu/drm/drm_client.c:226
 drm_lastclose drivers/gpu/drm/drm_file.c:467 [inline]
 drm_release+0x4dc/0x654 drivers/gpu/drm/drm_file.c:498
 __fput+0x1c4/0x800 fs/file_table.c:280
 ____fput+0x20/0x30 fs/file_table.c:308
 task_work_run+0x130/0x1e4 kernel/task_work.c:188
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0x670/0x20bc kernel/exit.c:874
 do_group_exit+0x110/0x268 kernel/exit.c:996
 __do_sys_exit_group kernel/exit.c:1007 [inline]
 __se_sys_exit_group kernel/exit.c:1005 [inline]
 __wake_up_parent+0x0/0x60 kernel/exit.c:1005
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
irq event stamp: 1502
hardirqs last  enabled at (1501): [<ffff800011b96d64>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline]
hardirqs last  enabled at (1501): [<ffff800011b96d64>] _raw_spin_unlock_irq+0x9c/0x134 kernel/locking/spinlock.c:202
hardirqs last disabled at (1502): [<ffff800011b96780>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:126 [inline]
hardirqs last disabled at (1502): [<ffff800011b96780>] _raw_spin_lock_irq+0x38/0x13c kernel/locking/spinlock.c:170
softirqs last  enabled at (986): [<ffff8000080308b0>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:31
softirqs last disabled at (984): [<ffff80000803087c>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:18
---[ end trace a48bb08d33d6dd86 ]---

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/09 19:21 linux-5.15.y 3c17fc483905 6b856513 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in vkms_get_vblank_timestamp
2024/10/05 17:58 linux-5.15.y 3a5928702e71 d7906eff .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in vkms_get_vblank_timestamp
* Struck through repros no longer work on HEAD.