device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 INFO: task syz-executor0:32723 blocked for more than 140 seconds. b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 Not tainted 5.0.0-rc1+ #21 b_state=0x00000029, b_size=512 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 syz-executor0 D27144 32723 8012 0x00000004 b_state=0x00000029, b_size=512 Call Trace: device loop0 blocksize: 4096 context_switch kernel/sched/core.c:2831 [inline] __schedule+0x897/0x1e60 kernel/sched/core.c:3472 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 schedule+0xfe/0x350 kernel/sched/core.c:3516 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 __rwsem_down_write_failed_common+0xa4d/0x1620 kernel/locking/rwsem-xadd.c:577 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:606 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0xa5/0x130 kernel/locking/rwsem.c:72 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 inode_lock include/linux/fs.h:757 [inline] do_last fs/namei.c:3321 [inline] path_openat+0x1967/0x5650 fs/namei.c:3534 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 do_filp_open+0x26f/0x370 fs/namei.c:3564 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 do_sys_open+0x59a/0x7c0 fs/open.c:1063 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 __do_sys_open fs/open.c:1081 [inline] __se_sys_open fs/open.c:1076 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1076 device loop0 blocksize: 4096 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 entry_SYSCALL_64_after_hwframe+0x49/0xbe __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 RIP: 0033:0x457ec9 b_state=0x00000029, b_size=512 Code: 28 c3 e8 aa 20 00 00 eb a8 cc cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 2e 48 83 ec 18 48 89 6c 24 10 48 <8d> 6c 24 10 48 8b 42 08 48 8b 4a 10 48 89 04 24 48 89 4c 24 08 e8 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 RSP: 002b:00007fd09881ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 0000000000141042 RDI: 0000000020000140 RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd09881b6d4 R13: 00000000004f471f R14: 00000000004d6d30 R15: 00000000ffffffff b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 INFO: task syz-executor0:32724 blocked for more than 140 seconds. b_state=0x00000029, b_size=512 Not tainted 5.0.0-rc1+ #21 device loop0 blocksize: 4096 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D28376 32724 8012 0x00000004 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 Call Trace: b_state=0x00000029, b_size=512 context_switch kernel/sched/core.c:2831 [inline] __schedule+0x897/0x1e60 kernel/sched/core.c:3472 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 schedule+0xfe/0x350 kernel/sched/core.c:3516 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xa3b/0x1670 kernel/locking/mutex.c:1072 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __fdget_pos+0x1b3/0x1f0 fs/file.c:795 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 fdget_pos include/linux/file.h:70 [inline] ksys_write+0x81/0x260 fs/read_write.c:593 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 b_state=0x00000029, b_size=512 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 entry_SYSCALL_64_after_hwframe+0x49/0xbe device loop0 blocksize: 4096 RIP: 0033:0x457ec9 __find_get_block_slow() failed. block=1, b_blocknr=8 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 b_state=0x00000029, b_size=512 RSP: 002b:00007fd0987f9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 b_state=0x00000029, b_size=512 RDX: 00000000fffffc41 RSI: 0000000020001440 RDI: 0000000000000003 device loop0 blocksize: 4096 RBP: 000000000073c0e0 R08: 0000000000000000 R09: 0000000000000000 __find_get_block_slow() failed. block=1, b_blocknr=8 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd0987fa6d4 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 R13: 00000000004c7032 R14: 00000000004dc700 R15: 00000000ffffffff b_state=0x00000029, b_size=512 Showing all locks held in the system: device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 1 lock held by khungtaskd/1040: b_state=0x00000029, b_size=512 #0: 00000000ef3701eb (rcu_read_lock){....}, at: debug_show_all_locks+0xc6/0x41d kernel/locking/lockdep.c:4389 device loop0 blocksize: 4096 1 lock held by rsyslogd/7850: #0: 00000000c2450213 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1b3/0x1f0 fs/file.c:795 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/7972: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 #0: 00000000a237fbfc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000d7627bbb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/7973: b_state=0x00000029, b_size=512 #0: 000000007d963ea9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 device loop0 blocksize: 4096 #1: 0000000069c37b4a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/7974: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 #0: 000000002e1dd436 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008353b2ba (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/7975: b_state=0x00000029, b_size=512 #0: 00000000fd3f1d25 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 device loop0 blocksize: 4096 #1: 000000009b6726ed (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 2 locks held by getty/7976: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 #0: 00000000564c7040 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000001fb25340 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7977: #0: 0000000090181aff (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000044c41baa (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7978: #0: 000000000d0f86d7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000005c2f89b5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 3 locks held by kworker/u4:3/4962: 9 locks held by syz-executor0/32686: 2 locks held by syz-executor0/32695: 2 locks held by syz-executor0/32723: #0: 00000000d33e9f3e (sb_writers#14){.+.+}, at: sb_start_write include/linux/fs.h:1602 [inline] #0: 00000000d33e9f3e (sb_writers#14){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:357 #1: 000000008f440c1e (&sb->s_type->i_mutex_key#21){++++}, at: inode_lock include/linux/fs.h:757 [inline] #1: 000000008f440c1e (&sb->s_type->i_mutex_key#21){++++}, at: do_last fs/namei.c:3321 [inline] #1: 000000008f440c1e (&sb->s_type->i_mutex_key#21){++++}, at: path_openat+0x1967/0x5650 fs/namei.c:3534 1 lock held by syz-executor0/32724: #0: 000000003a3c1c6d (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1b3/0x1f0 fs/file.c:795 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1040 Comm: khungtaskd Not tainted 5.0.0-rc1+ #21 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+0x1db/0x2d0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62 __find_get_block_slow() failed. block=1, b_blocknr=8 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 b_state=0x00000029, b_size=512 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0xbbb/0x1170 kernel/hung_task.c:287 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: device loop0 blocksize: 4096 NMI backtrace for cpu 0 CPU: 0 PID: 4962 Comm: kworker/u4:3 Not tainted 5.0.0-rc1+ #21 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:450 Code: e9 00 00 00 49 8d 7c 24 38 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 17 41 03 5c 24 38 89 da ec <5b> 0f b6 c0 41 5c 5d c3 e8 58 4f e4 fd eb c2 e8 b1 4f e4 fd eb e2 RSP: 0018:ffff88804f336590 EFLAGS: 00000006 RAX: dffffc0000000005 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: ffffffff83e192e1 RDI: ffffffff8bf721f8 RBP: ffff88804f3365a0 R08: 1ffff11009e66ca2 R09: ffffed1009e66ca3 R10: ffffed1009e66ca2 R11: 0000000000000003 R12: ffffffff8bf721c0 R13: 000000000000004d R14: ffff88804f336698 R15: ffffffff8bf72208 FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000000a8124000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_port_in include/linux/serial_core.h:273 [inline] serial8250_console_write+0x291/0xab0 drivers/tty/serial/8250/8250_port.c:3250 univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:586 call_console_drivers kernel/printk/printk.c:1737 [inline] console_unlock+0xcff/0x11e0 kernel/printk/printk.c:2408 vprintk_emit+0x370/0x960 kernel/printk/printk.c:1931 vprintk_default+0x28/0x30 kernel/printk/printk.c:1958 vprintk_func+0x7e/0x189 kernel/printk/printk_safe.c:398 printk+0xba/0xed kernel/printk/printk.c:1991 __find_get_block_slow fs/buffer.c:237 [inline] __find_get_block fs/buffer.c:1294 [inline] __find_get_block.cold+0xd4/0xfb fs/buffer.c:1288 __getblk_slow fs/buffer.c:1039 [inline] __getblk_gfp+0x295/0xd20 fs/buffer.c:1320 __bread_gfp+0x2f/0x300 fs/buffer.c:1354 sb_bread include/linux/buffer_head.h:307 [inline] __fat_write_inode+0x33a/0xb70 fs/fat/inode.c:859 fat_write_inode+0x96/0x190 fs/fat/inode.c:908 write_inode fs/fs-writeback.c:1176 [inline] __writeback_single_inode+0xef1/0x1620 fs/fs-writeback.c:1375 writeback_sb_inodes+0x762/0x1260 fs/fs-writeback.c:1580 __writeback_inodes_wb+0x16d/0x3d0 fs/fs-writeback.c:1649 wb_writeback+0xa2d/0xf70 fs/fs-writeback.c:1758 wb_check_old_data_flush fs/fs-writeback.c:1860 [inline] wb_do_writeback fs/fs-writeback.c:1913 [inline] wb_workfn+0xf7f/0x16f0 fs/fs-writeback.c:1942 process_one_work+0xd0c/0x1ce0 kernel/workqueue.c:2153 worker_thread+0x143/0x14a0 kernel/workqueue.c:2296 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.480 msecs __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096