[[0;32m OK [0m] Reached target Login Prompts.
[[0;32m OK [0m] Reached target Multi-User System.
[[0;32m OK [0m] Reached target Graphical Interface.
Starting Update UTMP about System Runlevel Changes...
[[0;32m OK [0m] Started Update UTMP about System Runlevel Changes.
Debian GNU/Linux 9 syzkaller ttyS0
Warning: Permanently added '10.128.1.20' (ECDSA) to the list of known hosts.
executing program
syzkaller login: [ 489.534839][ T8465] block nbd0: shutting down sockets
[ 721.376453][ T1644] INFO: task syz-executor645:8465 blocked for more than 143 seconds.
[ 721.384674][ T1644] Not tainted 5.11.0-syzkaller #0
[ 721.391822][ T1644] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 721.401000][ T1644] task:syz-executor645 state:D stack:28256 pid: 8465 ppid: 8464 flags:0x00004004
[ 721.410357][ T1644] Call Trace:
[ 721.413674][ T1644] __schedule+0x999/0xe70
[ 721.418243][ T1644] schedule+0x14b/0x200
[ 721.422414][ T1644] schedule_timeout+0x43/0x250
[ 721.427272][ T1644] ? _raw_spin_unlock_irq+0x1f/0x40
[ 721.432478][ T1644] ? lockdep_hardirqs_on+0x8d/0x130
[ 721.437740][ T1644] do_wait_for_common+0x266/0x3a0
[ 721.442794][ T1644] ? console_conditional_schedule+0x30/0x30
[ 721.448809][ T1644] wait_for_completion+0x43/0x50
[ 721.453769][ T1644] flush_workqueue+0x704/0x1620
[ 721.458806][ T1644] nbd_ioctl+0x76d/0x940
[ 721.463150][ T1644] ? init_wait_entry+0xd0/0xd0
[ 721.468047][ T1644] ? nbd_release+0x120/0x120
[ 721.472646][ T1644] blkdev_ioctl+0x2d6/0x5f0
[ 721.477463][ T1644] block_ioctl+0xae/0xf0
[ 721.481839][ T1644] ? blkdev_iopoll+0xf0/0xf0
[ 721.486537][ T1644] __se_sys_ioctl+0xfb/0x170
[ 721.491206][ T1644] do_syscall_64+0x2d/0x70
[ 721.495647][ T1644] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 721.501605][ T1644] RIP: 0033:0x4441e9
[ 721.505524][ T1644] RSP: 002b:00007ffc87363948 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[ 721.514089][ T1644] RAX: ffffffffffffffda RBX: 00000000004004a0 RCX: 00000000004441e9
[ 721.522157][ T1644] RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
[ 721.530235][ T1644] RBP: 0000000000000000 R08: 00007ffc87363ae8 R09: 00007ffc87363ae8
[ 721.538310][ T1644] R10: 00007ffc87363ae8 R11: 0000000000000246 R12: 0000000000403500
[ 721.546409][ T1644] R13: 431bde82d7b634db R14: 00000000004b2018 R15: 00000000004004a0
[ 721.554446][ T1644]
[ 721.554446][ T1644] Showing all locks held in the system:
[ 721.562349][ T1644] 1 lock held by khungtaskd/1644:
[ 721.567502][ T1644] #0: ffffffff8c711680 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
[ 721.577023][ T1644] 3 locks held by kworker/u5:0/2034:
[ 721.582311][ T1644] #0: ffff888016152938 ((wq_completion)knbd0-recv){+.+.}-{0:0}, at: process_one_work+0x6f4/0xfc0
[ 721.593034][ T1644] #1: ffffc900072afd78 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x733/0xfc0
[ 721.604226][ T1644] #2: ffff888018ca7120 (sk_lock-AF_AX25){+.+.}-{0:0}, at: ax25_recvmsg+0x86/0x740
[ 721.613816][ T1644] 1 lock held by in:imklog/8097:
[ 721.618890][ T1644] #0: ffff8880198b14f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0
[ 721.629281][ T1644]
[ 721.631663][ T1644] =============================================
[ 721.631663][ T1644]
[ 721.640468][ T1644] NMI backtrace for cpu 1
[ 721.644820][ T1644] CPU: 1 PID: 1644 Comm: khungtaskd Not tainted 5.11.0-syzkaller #0
[ 721.652924][ T1644] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 721.664093][ T1644] Call Trace:
[ 721.667393][ T1644] dump_stack+0x137/0x1be
[ 721.671829][ T1644] ? nmi_cpu_backtrace+0x94/0x190
[ 721.676839][ T1644] ? hw_nmi_get_sample_period+0x30/0x60
[ 721.682451][ T1644] nmi_cpu_backtrace+0x16c/0x190
[ 721.687392][ T1644] ? arch_trigger_cpumask_backtrace+0x10/0x10
[ 721.695135][ T1644] nmi_trigger_cpumask_backtrace+0x191/0x2f0
[ 721.701126][ T1644] ? arch_trigger_cpumask_backtrace+0x10/0x10
[ 721.707198][ T1644] watchdog+0xce9/0xd30
[ 721.711458][ T1644] ? hungtask_pm_notify+0x50/0x50
[ 721.717251][ T1644] kthread+0x39a/0x3c0
[ 721.721364][ T1644] ? hungtask_pm_notify+0x50/0x50
[ 721.726380][ T1644] ? kthread_blkcg+0xd0/0xd0
[ 721.730983][ T1644] ret_from_fork+0x1f/0x30
[ 721.735576][ T1644] Sending NMI from CPU 1 to CPUs 0:
[ 721.741258][ C0] NMI backtrace for cpu 0
[ 721.741269][ C0] CPU: 0 PID: 4866 Comm: systemd-journal Not tainted 5.11.0-syzkaller #0
[ 721.741275][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 721.741281][ C0] RIP: 0010:rw_verify_area+0xef/0x370
[ 721.741287][ C0] Code: 49 8d 9f 20 02 00 00 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 55 a5 f6 ff 48 83 3b 00 <74> 6f 49 8d 5f 28 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff
[ 721.741295][ C0] RSP: 0018:ffffc9000167fde0 EFLAGS: 00000246
[ 721.741306][ C0] RAX: 1ffff110280e66bc RBX: ffff8881407335e0 RCX: dffffc0000000000
[ 721.741311][ C0] RDX: 0000000000000000 RSI: 0000000000002000 RDI: ffffffffffffffff
[ 721.741316][ C0] RBP: ffffc9000167ff00 R08: ffffffff81c4ad94 R09: ffffed1004612f81
[ 721.741321][ C0] R10: ffffed1004612f81 R11: 0000000000000000 R12: 0000000000000000
[ 721.741326][ C0] R13: 0000000000000000 R14: 0000000000002000 R15: ffff8881407333c0
[ 721.741331][ C0] FS: 00007f86aed678c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
[ 721.741335][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 721.741340][ C0] CR2: 00007f86ac137000 CR3: 0000000012623000 CR4: 00000000001506f0
[ 721.741345][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 721.741350][ C0] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 721.741354][ C0] Call Trace:
[ 721.741357][ C0] vfs_read+0x168/0xa80
[ 721.741361][ C0] ? __fdget_pos+0x1d8/0x2f0
[ 721.741364][ C0] ksys_read+0x11b/0x220
[ 721.741368][ C0] do_syscall_64+0x2d/0x70
[ 721.741372][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 721.741376][ C0] RIP: 0033:0x7f86ae2f6210
[ 721.741381][ C0] Code: 73 01 c3 48 8b 0d 98 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 c1 20 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 4e fc ff ff 48 89 04 24
[ 721.741389][ C0] RSP: 002b:00007ffc24b39f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[ 721.741397][ C0] RAX: ffffffffffffffda RBX: 00007ffc24b3c9f0 RCX: 00007f86ae2f6210
[ 721.741402][ C0] RDX: 0000000000002000 RSI: 00007ffc24b3a7f0 RDI: 0000000000000009
[ 721.741407][ C0] RBP: 0000000000000000 R08: 0000000000000008 R09: 0000000000000070
[ 721.741412][ C0] R10: 00007ffc24bb6118 R11: 0000000000000246 R12: 00007ffc24b3a7f0
[ 721.741417][ C0] R13: 00007ffc24b3c948 R14: 00005570d8efb958 R15: 0005bb6e4751e476
[ 721.741915][ T1644] Kernel panic - not syncing: hung_task: blocked tasks
[ 721.983471][ T1644] CPU: 1 PID: 1644 Comm: khungtaskd Not tainted 5.11.0-syzkaller #0
[ 721.991456][ T1644] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 722.001502][ T1644] Call Trace:
[ 722.004775][ T1644] dump_stack+0x137/0x1be
[ 722.009099][ T1644] ? panic+0x1f3/0x800
[ 722.013238][ T1644] panic+0x291/0x800
[ 722.017119][ T1644] ? printk_safe_flush+0x18f/0x1c0
[ 722.022269][ T1644] ? nmi_trigger_cpumask_backtrace+0x236/0x2f0
[ 722.028424][ T1644] ? nmi_trigger_cpumask_backtrace+0x23f/0x2f0
[ 722.034564][ T1644] ? arch_trigger_cpumask_backtrace+0x10/0x10
[ 722.041439][ T1644] watchdog+0xd29/0xd30
[ 722.045628][ T1644] ? hungtask_pm_notify+0x50/0x50
[ 722.050658][ T1644] kthread+0x39a/0x3c0
[ 722.054729][ T1644] ? hungtask_pm_notify+0x50/0x50
[ 722.059739][ T1644] ? kthread_blkcg+0xd0/0xd0
[ 722.064349][ T1644] ret_from_fork+0x1f/0x30
[ 722.068987][ T1644] Kernel Offset: disabled
[ 722.073316][ T1644] Rebooting in 86400 seconds..