FAT-fs (loop0): Directory bread(block 10771) failed FAT-fs (loop0): Directory bread(block 10772) failed NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 INFO: task syz-executor.5:29079 blocked for more than 140 seconds. Not tainted 4.19.131-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27984 29079 6896 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x90e/0xef0 kernel/time/timer.c:1782 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common+0x29c/0x470 kernel/sched/completion.c:115 flush_workqueue+0x40b/0x13e0 kernel/workqueue.c:2715 nbd_start_device_ioctl drivers/block/nbd.c:1262 [inline] __nbd_ioctl drivers/block/nbd.c:1333 [inline] nbd_ioctl+0x759/0xbe0 drivers/block/nbd.c:1373 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x5cb/0x1a7e block/ioctl.c:601 block_ioctl+0xe9/0x130 fs/block_dev.c:1896 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45cb29 Code: Bad RIP value. RSP: 002b:00007f8a9bd10c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e9c20 RCX: 000000000045cb29 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000006 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000417 R14: 00000000004c6e7d R15: 00007f8a9bd116d4 Showing all locks held in the system: 1 lock held by khungtaskd/1079: #0: 000000004b3ad95c (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440 1 lock held by in:imklog/6133: #0: 000000004e25e402 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by kworker/u5:1/8743: #0: 0000000054f5ec14 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2126 #1: 00000000484dac74 ((work_completion)(&args->work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2130 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1079 Comm: khungtaskd Not tainted 4.19.131-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2fe lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x30b/0x410 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 4.19.131-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0xfb/0x3ff0 kernel/locking/lockdep.c:3291 Code: 00 44 8b 0d 07 31 cb 07 45 85 c9 0f 84 a4 00 00 00 48 c7 c2 a0 da 8f 8b 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 14 02 <48> c7 c0 a0 da 8f 8b 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 b7 RSP: 0000:ffff8880a9f07980 EFLAGS: 00000802 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffffffff8ba6f4a0 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000005 R11: 0000000000000000 R12: 0000000000000001 R13: ffff8880a9ef8240 R14: ffffffff8ba6f4a0 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002b667565 CR3: 0000000050fc6000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3907 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:152 debug_object_active_state lib/debugobjects.c:725 [inline] debug_object_active_state+0x104/0x330 lib/debugobjects.c:713 debug_rcu_head_unqueue kernel/rcu/rcu.h:202 [inline] rcu_do_batch kernel/rcu/tree.c:2583 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2897 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2864 [inline] rcu_process_callbacks+0x9af/0x18b0 kernel/rcu/tree.c:2881 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292 run_ksoftirqd+0x57/0x110 kernel/softirq.c:653 smpboot_thread_fn+0x655/0x9e0 kernel/smpboot.c:164 kthread+0x30b/0x410 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415