syzbot

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WARNING: CPU: 1 PID: 4305 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: 4305 Comm: syz-executor345 Not tainted 6.1.119-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 : ffff8000211570b0
x29: ffff8000211570b0 x28: ffff800021157170 x27: ffff0000cddf8ee8
x26: ffff800021157160 x25: 1ffff0000422ae2e x24: 0000000000000000
x23: ffff0000cddf8000 x22: dfff800000000000 x21: 00000008a8fc5e81
x20: 00000008a8fc5e81 x19: ffff800021157170 x18: ffff8000211570e0
x17: 0048000000000326 x16: ffff8000083192b4 x15: 0000000000000000
x14: 1ffff00002b500b2 x13: dfff800000000000 x12: ffff70000422ae28
x11: 0000000000ff0100 x10: 0000000000000000 x9 : ffff80000bb09c14
x8 : ffff0000da560000 x7 : ffff80000b95049c x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : ffff800021157170 x1 : 00000008a8fc5e81 x0 : 00000008a8fc5e81
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:1061
 drm_client_modeset_commit_locked+0xd0/0x4a8 drivers/gpu/drm/drm_client_modeset.c:1164
 drm_client_modeset_commit+0x50/0x7c drivers/gpu/drm/drm_client_modeset.c:1190
 __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+0x1c8/0x7c8 fs/file_table.c:320
 ____fput+0x20/0x30 fs/file_table.c:348
 task_work_run+0x240/0x2f0 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0x554/0x1a88 kernel/exit.c:871
 do_group_exit+0x194/0x22c kernel/exit.c:1021
 __do_sys_exit_group kernel/exit.c:1032 [inline]
 __se_sys_exit_group kernel/exit.c:1030 [inline]
 __wake_up_parent+0x0/0x60 kernel/exit.c:1030
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 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: 1398
hardirqs last  enabled at (1397): [<ffff800012407074>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline]
hardirqs last  enabled at (1397): [<ffff800012407074>] _raw_spin_unlock_irq+0x3c/0x90 kernel/locking/spinlock.c:202
hardirqs last disabled at (1398): [<ffff800012406e34>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:117 [inline]
hardirqs last disabled at (1398): [<ffff800012406e34>] _raw_spin_lock_irq+0x34/0x9c kernel/locking/spinlock.c:170
softirqs last  enabled at (716): [<ffff800008030310>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (714): [<ffff8000080302dc>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---