EXT4-fs (loop0): re-mounted. Opts: (null) EXT4-fs (loop0): re-mounted. Opts: (null) EXT4-fs (loop0): re-mounted. Opts: (null) EXT4-fs (loop0): re-mounted. Opts: (null) INFO: task syz-executor306:7964 blocked for more than 140 seconds. Not tainted 4.14.294-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor306 D28448 7964 7962 0x00000000 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_timeout+0x80a/0xe90 kernel/time/timer.c:1724 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common+0x272/0x430 kernel/sched/completion.c:123 kthread_stop+0xce/0x640 kernel/kthread.c:555 ext4_put_super+0x865/0xf00 fs/ext4/super.c:988 generic_shutdown_super+0x144/0x370 fs/super.c:446 kill_block_super+0x95/0xe0 fs/super.c:1161 deactivate_locked_super+0x6c/0xd0 fs/super.c:319 deactivate_super+0x7f/0xa0 fs/super.c:350 cleanup_mnt+0x186/0x2c0 fs/namespace.c:1183 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f0273962657 RSP: 002b:00007ffe3461bc08 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f0273962657 RDX: 00007ffe3461bccb RSI: 000000000000000a RDI: 00007ffe3461bcc0 RBP: 00007ffe3461bcc0 R08: 00000000ffffffff R09: 00007ffe3461baa0 R10: 0000555555608683 R11: 0000000000000202 R12: 00007ffe3461cd30 R13: 00005555556085f0 R14: 00007ffe3461bc30 R15: 00000000000000d4 Showing all locks held in the system: 1 lock held by khungtaskd/1535: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 1 lock held by syz-executor306/7964: #0: (&type->s_umount_key#38){++++}, at: [] deactivate_super+0x77/0xa0 fs/super.c:349 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1535 Comm: khungtaskd Not tainted 4.14.294-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4625 Comm: systemd-journal Not tainted 4.14.294-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 task: ffff8880a122a180 task.stack: ffff8880a1230000 RIP: 0010:__sanitizer_cov_trace_pc+0x23/0x50 kernel/kcov.c:68 RSP: 0018:ffff8880a1237cf8 EFLAGS: 00000246 RAX: ffff8880a122a180 RBX: 0000000000002068 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000800000 RDI: ffff8880a0c4c10c RBP: ffff8880a1237e20 R08: ffffffff8b9c9a28 R09: 0000000000000000 R10: ffff8880a122aa30 R11: 0000000000000000 R12: ffff8880a5fc2b80 R13: 0000000000000000 R14: ffff8880a0c4c100 R15: 0000000000000000 FS: 00007f36852028c0(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f36825e4010 CR3: 00000000a14c5000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: setattr_prepare+0x80/0x530 fs/attr.c:62 shmem_setattr+0x98/0xbf0 mm/shmem.c:1017 notify_change+0x56b/0xd10 fs/attr.c:315 do_truncate+0xff/0x1a0 fs/open.c:63 do_sys_ftruncate.constprop.0+0x3a3/0x480 fs/open.c:205 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f36844c4ec7 RSP: 002b:00007ffc4b5ddd68 EFLAGS: 00000202 ORIG_RAX: 000000000000004d RAX: ffffffffffffffda RBX: 00007ffc4b5ddda0 RCX: 00007f36844c4ec7 RDX: 000055ee483ffe80 RSI: 0000000000800000 RDI: 0000000000000010 RBP: 00007ffc4b5ddd98 R08: 0000000000000008 R09: 000055ee4840025c R10: 000055ee484001e0 R11: 0000000000000202 R12: 000055ee484001e0 R13: 00007ffc4b5dde98 R14: 000055ee46c30958 R15: 0005e97e24e8618f Code: 90 90 90 90 90 90 90 90 65 48 8b 04 25 c0 7f 02 00 48 85 c0 74 1a 65 8b 15 7b 37 ad 7e 81 e2 00 01 1f 00 75 0b 8b 90 58 13 00 00 <83> fa 01 74 01 c3 48 8b 34 24 48 8b 88 60 13 00 00 8b 80 5c 13