[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 66.678910][ T26] audit: type=1800 audit(1559578854.971:25): pid=8773 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 66.715358][ T26] audit: type=1800 audit(1559578854.971:26): pid=8773 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 66.773257][ T26] audit: type=1800 audit(1559578854.971:27): pid=8773 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.12' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 74.898884][ T8928] [drm:drm_calc_timestamping_constants] *ERROR* crtc 31: Can't calculate constants, dotclock = 0! [ 74.910885][ C1] WARNING: CPU: 1 PID: 8928 at drivers/gpu/drm/vkms/vkms_crtc.c:40 vkms_vblank_simulate+0x25c/0x2c0 [ 74.922000][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 74.928579][ C1] CPU: 1 PID: 8928 Comm: syz-executor016 Not tainted 5.2.0-rc3 #10 [ 74.936624][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 74.946688][ C1] Call Trace: [ 74.949991][ C1] [ 74.952996][ C1] dump_stack+0x172/0x1f0 [ 74.957324][ C1] ? vkms_vblank_simulate+0x1d0/0x2c0 [ 74.963065][ C1] panic+0x2cb/0x744 [ 74.966945][ C1] ? __warn_printk+0xf3/0xf3 [ 74.971613][ C1] ? vkms_vblank_simulate+0x25c/0x2c0 [ 74.977329][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 74.984304][ C1] ? __warn.cold+0x5/0x4d [ 74.988624][ C1] ? __warn+0xe8/0x1d0 [ 74.992751][ C1] ? vkms_vblank_simulate+0x25c/0x2c0 [ 74.998270][ C1] __warn.cold+0x20/0x4d [ 75.002509][ C1] ? vkms_vblank_simulate+0x25c/0x2c0 [ 75.008252][ C1] report_bug+0x263/0x2b0 [ 75.012616][ C1] do_error_trap+0x11b/0x200 [ 75.018088][ C1] do_invalid_op+0x37/0x50 [ 75.022538][ C1] ? vkms_vblank_simulate+0x25c/0x2c0 [ 75.027935][ C1] invalid_op+0x14/0x20 [ 75.032103][ C1] RIP: 0010:vkms_vblank_simulate+0x25c/0x2c0 [ 75.038084][ C1] Code: c7 c7 40 2c c0 87 e8 33 08 ba ff e9 32 fe ff ff e8 39 0f 93 fd 48 8b 45 d0 49 89 86 40 02 00 00 e9 7a ff ff ff e8 24 0f 93 fd <0f> 0b e9 f4 fe ff ff e8 e8 ac cb fd e9 3a fe ff ff e8 3e ad cb fd [ 75.057925][ C1] RSP: 0018:ffff8880ae909dd8 EFLAGS: 00010006 [ 75.064092][ C1] RAX: ffff88808b22c700 RBX: ffff8880ae926d80 RCX: ffffffff83dd967d [ 75.072049][ C1] RDX: 0000000000010000 RSI: ffffffff83dd978c RDI: 0000000000000007 [ 75.080011][ C1] RBP: ffff8880ae909e08 R08: ffff88808b22c700 R09: 0000000000000002 [ 75.087969][ C1] R10: fffffbfff14c2b64 R11: ffff88808b22c700 R12: 0000000000093d7d [ 75.095936][ C1] R13: ffff888219195890 R14: 0000000000000000 R15: ffff888219194d88 [ 75.104175][ C1] ? vkms_vblank_simulate+0x14d/0x2c0 [ 75.109555][ C1] ? vkms_vblank_simulate+0x25c/0x2c0 [ 75.114957][ C1] ? vkms_vblank_simulate+0x25c/0x2c0 [ 75.120335][ C1] __hrtimer_run_queues+0x33b/0xdd0 [ 75.125903][ C1] ? vkms_disable_vblank+0x20/0x20 [ 75.131105][ C1] ? hrtimer_start_range_ns+0xc70/0xc70 [ 75.136653][ C1] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 75.142365][ C1] ? ktime_get_update_offsets_now+0x2d3/0x440 [ 75.148450][ C1] hrtimer_interrupt+0x314/0x770 [ 75.153384][ C1] smp_apic_timer_interrupt+0x111/0x550 [ 75.158926][ C1] apic_timer_interrupt+0xf/0x20 [ 75.163860][ C1] [ 75.166798][ C1] RIP: 0010:_raw_spin_unlock_irqrestore+0x95/0xe0 [ 75.173197][ C1] Code: 48 c7 c0 f0 73 b2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 39 48 83 3d 62 d0 95 01 00 74 24 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 7c d8 30 fa 65 8b 05 dd 59 e5 78 [ 75.192973][ C1] RSP: 0018:ffff88808783fb10 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 [ 75.201376][ C1] RAX: 1ffffffff1164e7e RBX: 0000000000000286 RCX: 0000000000000000 [ 75.209365][ C1] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: 0000000000000286 [ 75.217698][ C1] RBP: ffff88808783fb20 R08: ffff88808b22c700 R09: 0000000000000000 [ 75.225763][ C1] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8882191944b0 [ 75.233731][ C1] R13: 0000000000000000 R14: ffff8882191944b0 R15: ffff8880a42d7b88 [ 75.241742][ C1] drm_vblank_get+0x150/0x1e0 [ 75.246408][ C1] drm_wait_vblank_ioctl+0x513/0x1950 [ 75.251856][ C1] ? drm_dev_exit+0x22/0x60 [ 75.256382][ C1] ? drm_legacy_modeset_ctl_ioctl+0x4a0/0x4a0 [ 75.262950][ C1] ? lock_downgrade+0x880/0x880 [ 75.267825][ C1] ? drm_dev_exit+0x60/0x60 [ 75.272321][ C1] drm_ioctl_kernel+0x244/0x300 [ 75.277164][ C1] ? drm_legacy_modeset_ctl_ioctl+0x4a0/0x4a0 [ 75.283227][ C1] ? drm_setversion+0x8c0/0x8c0 [ 75.288093][ C1] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 75.294358][ C1] ? _copy_from_user+0xdd/0x150 [ 75.299206][ C1] compat_drm_wait_vblank+0xd6/0x190 [ 75.304488][ C1] ? compat_drm_mode_addfb2+0x1a0/0x1a0 [ 75.310046][ C1] ? compat_drm_mode_addfb2+0x1a0/0x1a0 [ 75.315589][ C1] drm_compat_ioctl+0x1eb/0x310 [ 75.320633][ C1] ? security_file_ioctl+0x8d/0xc0 [ 75.325733][ C1] ? compat_drm_setunique+0x10/0x10 [ 75.331023][ C1] __ia32_compat_sys_ioctl+0x195/0x620 [ 75.336482][ C1] do_fast_syscall_32+0x27b/0xd7d [ 75.341501][ C1] entry_SYSENTER_compat+0x70/0x7f [ 75.346594][ C1] RIP: 0023:0xf7f12849 [ 75.350737][ C1] Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 [ 75.370337][ C1] RSP: 002b:00000000ffe2597c EFLAGS: 00000213 ORIG_RAX: 0000000000000036 [ 75.378952][ C1] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000c02c563a [ 75.386911][ C1] RDX: 0000000020000040 RSI: 00000000080ef078 RDI: 00000000ffe259d0 [ 75.394894][ C1] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 75.403180][ C1] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 75.411150][ C1] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 75.420589][ C1] Kernel Offset: disabled [ 75.425005][ C1] Rebooting in 86400 seconds..