syzbot


WARNING in vkms_get_vblank_timestamp

Status: upstream: reported C repro on 2024/03/14 22:37
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+7ff1b5bce8646c58d994@syzkaller.appspotmail.com
First crash: 70d, last: 2d11h
Bug presence (1)
Date Name Commit Repro Result
2024/03/15 upstream (ToT) e5eb28f6d1af C [report] WARNING in vkms_get_vblank_timestamp
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in vkms_get_vblank_timestamp dri syz error 41 354d 413d 22/26 fixed on 2023/06/08 14:41
upstream WARNING in vkms_get_vblank_timestamp (2) dri C done 258 5d03h 346d 0/26 upstream: reported C repro on 2023/06/13 03:40
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2024/05/22 01:06 1h46m bisect fix linux-6.1.y job log (0) log
2024/04/17 22:00 2h05m bisect fix linux-6.1.y job log (0) log

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4232 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: 4232 Comm: syz-executor318 Not tainted 6.1.81-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
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 : ffff80001dc071f0
x29: ffff80001dc071f0 x28: ffff80001dc072b0 x27: ffff0000cd494ee8
x26: ffff80001dc072a0 x25: 1ffff00003b80e56 x24: 0000000000000000
x23: ffff0000cd494000 x22: dfff800000000000 x21: 00000007bcb153c9
x20: 00000007bcb153c9 x19: ffff80001dc072b0 x18: ffff80001dc078c8
x17: 0000000000000000 x16: ffff80000831d00c x15: 0000000000000000
x14: 1ffff00002b060b0 x13: dfff800000000000 x12: ffff700003b80e50
x11: 0000000000ff0100 x10: 0000000000000000 x9 : ffff80000ba4d394
x8 : ffff0000dca2d340 x7 : ffff80000b8934b0 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : ffff80001dc072b0 x1 : 00000007bcb153c9 x0 : 00000007bcb153c9
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/0xb24 drivers/gpu/drm/drm_vblank.c:303
 drm_crtc_accurate_vblank_count+0x114/0x334 drivers/gpu/drm/drm_vblank.c:416
 drm_crtc_arm_vblank_event+0xa8/0x1e0 drivers/gpu/drm/drm_vblank.c:1066
 vkms_crtc_atomic_flush+0x1a8/0x1b4 drivers/gpu/drm/vkms/vkms_crtc.c:259
 drm_atomic_helper_commit_planes+0x7d4/0x8e0 drivers/gpu/drm/drm_atomic_helper.c:2732
 vkms_atomic_commit_tail+0x6c/0x20c drivers/gpu/drm/vkms/vkms_drv.c:73
 commit_tail+0x274/0x3b8 drivers/gpu/drm/drm_atomic_helper.c:1803
 drm_atomic_helper_commit+0x5fc/0x644 drivers/gpu/drm/drm_atomic_helper.c:2043
 drm_atomic_commit+0x24c/0x2a0 drivers/gpu/drm/drm_atomic.c:1452
 drm_atomic_helper_set_config+0xe8/0x198 drivers/gpu/drm/drm_atomic_helper.c:3176
 drm_mode_setcrtc+0x918/0x13e8 drivers/gpu/drm/drm_crtc.c:886
 drm_ioctl_kernel+0x2cc/0x458 drivers/gpu/drm/drm_ioctl.c:788
 drm_ioctl+0x5a0/0xa2c drivers/gpu/drm/drm_ioctl.c:891
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 716
hardirqs last  enabled at (715): [<ffff8000122297ec>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline]
hardirqs last  enabled at (715): [<ffff8000122297ec>] _raw_spin_unlock_irq+0x3c/0x90 kernel/locking/spinlock.c:202
hardirqs last disabled at (716): [<ffff8000122295ac>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:117 [inline]
hardirqs last disabled at (716): [<ffff8000122295ac>] _raw_spin_lock_irq+0x34/0x9c kernel/locking/spinlock.c:170
softirqs last  enabled at (482): [<ffff800008033178>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (480): [<ffff800008033144>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4232 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: 1 PID: 4232 Comm: syz-executor318 Tainted: G        W          6.1.81-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
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 : ffff80001dc070b0
x29: ffff80001dc070b0 x28: ffff80001dc07170 x27: ffff0000cd494ee8
x26: ffff80001dc07160 x25: 1ffff00003b80e2e x24: 0000000000000000
x23: ffff0000cd494000 x22: dfff800000000000 x21: 00000007c2400989
x20: 00000007c2400989 x19: ffff80001dc07170 x18: ffff80001dc07060
x17: 0048000000000326 x16: ffff80000831d00c x15: 0000000000000000
x14: 1ffff00002b060b0 x13: dfff800000000000 x12: ffff700003b80e28
x11: 0000000000ff0100 x10: 0000000000000000 x9 : ffff80000ba4d394
x8 : ffff0000dca2d340 x7 : ffff80000b894290 x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : ffff80001dc07170 x1 : 00000007c2400989 x0 : 00000007c2400989
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/0xb24 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+0x258/0x7b8 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:1227 [inline]
 drm_atomic_helper_commit_modeset_disables+0xab0/0x15bc drivers/gpu/drm/drm_atomic_helper.c:1431
 vkms_atomic_commit_tail+0x5c/0x20c drivers/gpu/drm/vkms/vkms_drv.c:71
 commit_tail+0x274/0x3b8 drivers/gpu/drm/drm_atomic_helper.c:1803
 drm_atomic_helper_commit+0x5fc/0x644 drivers/gpu/drm/drm_atomic_helper.c:2043
 drm_atomic_commit+0x24c/0x2a0 drivers/gpu/drm/drm_atomic.c:1452
 drm_client_modeset_commit_atomic+0x5a4/0x730 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:253 [inline]
 drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:280 [inline]
 drm_fb_helper_lastclose drivers/gpu/drm/drm_fb_helper.c:2106 [inline]
 drm_fbdev_client_restore+0xe8/0x17c drivers/gpu/drm/drm_fb_helper.c:2518
 drm_client_dev_restore+0x12c/0x24c drivers/gpu/drm/drm_client.c:247
 drm_lastclose drivers/gpu/drm/drm_file.c:462 [inline]
 drm_release+0x4dc/0x624 drivers/gpu/drm/drm_file.c:493
 __fput+0x30c/0x7bc fs/file_table.c:320
 ____fput+0x20/0x30 fs/file_table.c:348
 task_work_run+0x240/0x2f0 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0x554/0x1a88 kernel/exit.c:869
 do_group_exit+0x194/0x22c kernel/exit.c:1019
 __do_sys_exit_group kernel/exit.c:1030 [inline]
 __se_sys_exit_group kernel/exit.c:1028 [inline]
 __wake_up_parent+0x0/0x60 kernel/exit.c:1028
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 1510
hardirqs last  enabled at (1509): [<ffff8000122297ec>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline]
hardirqs last  enabled at (1509): [<ffff8000122297ec>] _raw_spin_unlock_irq+0x3c/0x90 kernel/locking/spinlock.c:202
hardirqs last disabled at (1510): [<ffff8000122295ac>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:117 [inline]
hardirqs last disabled at (1510): [<ffff8000122295ac>] _raw_spin_lock_irq+0x34/0x9c kernel/locking/spinlock.c:170
softirqs last  enabled at (932): [<ffff800008033178>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (930): [<ffff800008033144>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/15 03:36 linux-6.1.y 61adba85cc40 d615901c .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in vkms_get_vblank_timestamp
2024/03/14 22:36 linux-6.1.y 61adba85cc40 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in vkms_get_vblank_timestamp
* Struck through repros no longer work on HEAD.