FAT-fs (loop5): error, fat_get_cluster: invalid cluster chain (i_pos 16) FAT-fs (loop5): Filesystem has been set read-only FAT-fs (loop5): error, fat_get_cluster: invalid cluster chain (i_pos 16) INFO: task syz-executor2:8274 blocked for more than 140 seconds. Not tainted 4.9.124-g09eb2ba #31 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D28600 8274 3875 0x00000004 ffff880197b94800 0000000000000000 ffff8801c0034540 ffff8801ce28c800 ffff8801db321c18 ffff880196e373e0 ffffffff839f0afd ffffffff855bc730 ffff880197b95130 0000000000004626 00ff880197b950e0 ffff8801db3224e8 Call Trace: [] schedule+0x7f/0x1b0 kernel/sched/core.c:3553 [] schedule_timeout+0x861/0xf70 kernel/time/timer.c:1768 [] do_wait_for_common kernel/sched/completion.c:75 [inline] [] __wait_for_common kernel/sched/completion.c:93 [inline] [] wait_for_common kernel/sched/completion.c:101 [inline] [] wait_for_completion+0x203/0x2e0 kernel/sched/completion.c:122 [] flush_work+0x3a4/0x6c0 kernel/workqueue.c:2846 [] __cancel_work_timer+0x17e/0x440 kernel/workqueue.c:2912 [] cancel_work_sync+0x17/0x20 kernel/workqueue.c:2947 [] p9_conn_destroy net/9p/trans_fd.c:857 [inline] [] p9_fd_close+0x1f1/0x330 net/9p/trans_fd.c:883 [] p9_client_create+0x825/0x10a0 net/9p/client.c:1050 [] v9fs_session_init+0x333/0x13a0 fs/9p/v9fs.c:343 [] v9fs_mount+0x7d/0x810 fs/9p/vfs_super.c:130 [] mount_fs+0x28c/0x370 fs/super.c:1206 [] vfs_kern_mount.part.29+0xd1/0x3d0 fs/namespace.c:1000 [] vfs_kern_mount fs/namespace.c:982 [inline] [] do_new_mount fs/namespace.c:2537 [inline] [] do_mount+0x3c9/0x2740 fs/namespace.c:2859 [] SYSC_mount fs/namespace.c:3075 [inline] [] SyS_mount+0xfe/0x110 fs/namespace.c:3052 [] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Showing all locks held in the system: 2 locks held by khungtaskd/519: #0: (rcu_read_lock){......}, at: [] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline] #0: (rcu_read_lock){......}, at: [] watchdog+0x11c/0xa20 kernel/hung_task.c:239 #1: (tasklist_lock){.+.+..}, at: [] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336 2 locks held by kworker/1:2/1839: #0: ("events"){.+.+.+}, at: [] work_static include/linux/workqueue.h:186 [inline] #0: ("events"){.+.+.+}, at: [] set_work_data kernel/workqueue.c:617 [inline] #0: ("events"){.+.+.+}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: ("events"){.+.+.+}, at: [] process_one_work+0x6ee/0x1500 kernel/workqueue.c:2085 #1: ((&m->wq)){+.+.+.}, at: [] process_one_work+0x728/0x1500 kernel/workqueue.c:2089 1 lock held by rsyslogd/3665: #0: (&f->f_pos_lock){+.+.+.}, at: [] __fdget_pos+0xac/0xd0 fs/file.c:781 2 locks held by getty/3761: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.124-g09eb2ba #31 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801d912fd08 ffffffff81eb95e9 0000000000000000 0000000000000001 0000000000000001 0000000000000001 ffffffff810b9fa0 ffff8801d912fd40 ffffffff81ec4927 0000000000000001 0000000000000000 0000000000000003 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99 [] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60 [] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 [] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline] [] check_hung_task kernel/hung_task.c:125 [inline] [] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline] [] watchdog+0x6b4/0xa20 kernel/hung_task.c:239 [] kthread+0x26d/0x300 kernel/kthread.c:211 [] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff83a00606