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 INFO: task syz-executor0:6007 blocked for more than 140 seconds. b_state=0x00000029, b_size=512 Not tainted 4.20.0-rc1-next-20181109+ #110 device loop0 blocksize: 4096 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. __find_get_block_slow() failed. block=1, b_blocknr=8 syz-executor0 D18984 6007 1 0x00000004 b_state=0x00000029, b_size=512 Call Trace: device loop0 blocksize: 4096 context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 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=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 schedule+0xef/0x370 kernel/sched/core.c:3516 __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 wb_wait_for_completion+0x1f9/0x2d0 fs/fs-writeback.c:221 __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 __writeback_inodes_sb_nr+0x405/0x580 fs/fs-writeback.c:2333 __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 writeback_inodes_sb_nr fs/fs-writeback.c:2350 [inline] writeback_inodes_sb+0x27/0x30 fs/fs-writeback.c:2365 __find_get_block_slow() failed. block=1, b_blocknr=8 __sync_filesystem fs/sync.c:36 [inline] sync_filesystem+0x16f/0x330 fs/sync.c:64 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 generic_shutdown_super+0xdd/0x530 fs/super.c:441 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 kill_block_super+0x9e/0x100 fs/super.c:1383 __find_get_block_slow() failed. block=1, b_blocknr=8 deactivate_locked_super+0x97/0x100 fs/super.c:328 b_state=0x00000029, b_size=512 deactivate_super+0x2bb/0x320 fs/super.c:359 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 cleanup_mnt+0xbf/0x160 fs/namespace.c:1049 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 __cleanup_mnt+0x16/0x20 fs/namespace.c:1056 b_state=0x00000029, b_size=512 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 __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 entry_SYSCALL_64_after_hwframe+0x49/0xbe device loop0 blocksize: 4096 RIP: 0033:0x459fb7 Code: Bad RIP value. __find_get_block_slow() failed. block=1, b_blocknr=8 RSP: 002b:00007ffd2a02dd28 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000459fb7 b_state=0x00000029, b_size=512 RDX: 0000000000402e70 RSI: 0000000000000002 RDI: 00007ffd2a02ddd0 device loop0 blocksize: 4096 RBP: 0000000000000128 R08: 0000000000000000 R09: 000000000000000a __find_get_block_slow() failed. block=1, b_blocknr=8 R10: 0000000000000005 R11: 0000000000000206 R12: 00007ffd2a02ee60 R13: 0000000000b56940 R14: 0000000000000000 R15: 0000000000000000 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 5 locks held by kworker/u4:3/583: b_state=0x00000029, b_size=512 1 lock held by khungtaskd/990: device loop0 blocksize: 4096 #0: 00000000c38a74ed (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 __find_get_block_slow() failed. block=1, b_blocknr=8 1 lock held by rsyslogd/5876: b_state=0x00000029, b_size=512 #0: 00000000d0c46758 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 device loop0 blocksize: 4096 2 locks held by getty/5966: __find_get_block_slow() failed. block=1, b_blocknr=8 #0: 000000007a1f2fd8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 #1: 000000009e4843db (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 b_state=0x00000029, b_size=512 2 locks held by getty/5967: #0: 00000000c952d580 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 device loop0 blocksize: 4096 #1: 0000000099cca259 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/5968: b_state=0x00000029, b_size=512 #0: 000000001e7be0b9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 device loop0 blocksize: 4096 #1: 000000007cf7a7ba (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/5969: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 #0: 000000004f15e7ce (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 __find_get_block_slow() failed. block=1, b_blocknr=8 #1: 0000000050b556a2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 b_state=0x00000029, b_size=512 2 locks held by getty/5970: device loop0 blocksize: 4096 #0: 00000000791eefd6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 __find_get_block_slow() failed. block=1, b_blocknr=8 #1: 00000000a8c7ced5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 b_state=0x00000029, b_size=512 2 locks held by getty/5971: #0: 00000000a1f54628 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 device loop0 blocksize: 4096 #1: 0000000016a499d6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 __find_get_block_slow() failed. block=1, b_blocknr=8 2 locks held by getty/5972: b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 #0: 000000002c8f12f9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 #1: 000000006ed45d33 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 b_state=0x00000029, b_size=512 1 lock held by syz-executor0/6007: device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 #0: 00000000050c2523 (&fc->fs_type->s_umount_key#53){+.+.}, at: deactivate_super+0x2b3/0x320 fs/super.c:358 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 ============================================= NMI backtrace for cpu 0 __find_get_block_slow() failed. block=1, b_blocknr=8 CPU: 0 PID: 990 Comm: khungtaskd Not tainted 4.20.0-rc1-next-20181109+ #110 b_state=0x00000029, b_size=512 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+0x244/0x39d lib/dump_stack.c:113 device loop0 blocksize: 4096 nmi_cpu_backtrace.cold.2+0x5c/0xa1 lib/nmi_backtrace.c:101 __find_get_block_slow() failed. block=1, b_blocknr=8 nmi_trigger_cpumask_backtrace+0x1e8/0x22a lib/nmi_backtrace.c:62 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:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb4c/0x1060 kernel/hung_task.c:289 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 kthread+0x35a/0x440 kernel/kthread.c:246 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 __find_get_block_slow() failed. block=1, b_blocknr=8 Sending NMI from CPU 0 to CPUs 1: b_state=0x00000029, b_size=512 NMI backtrace for cpu 1 CPU: 1 PID: 583 Comm: kworker/u4:3 Not tainted 4.20.0-rc1-next-20181109+ #110 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:number+0xb76/0xca0 lib/vsprintf.c:518 Code: ff ff e8 4d 93 b5 f9 8b 9d 0c ff ff ff 83 eb 02 e9 58 fa ff ff e8 3a 93 b5 f9 83 eb 01 e9 fb fb ff ff 4d 89 fe e9 6f fd ff ff 25 93 b5 f9 48 8d 45 98 48 89 de 48 89 c7 48 89 c3 48 89 85 28 RSP: 0018:ffff8801d86f5b78 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 00000000000001a6 RCX: ffffffff87ca0d3c RDX: 000000000000000a RSI: 000000000000000a RDI: 0000000000000001 RBP: ffff8801d86f5c98 R08: ffff8801d86ee140 R09: ffffed003b0debca R10: ffffed003b0debca R11: 0000000000000003 R12: 000000000000000a R13: 000000000000000a R14: 0000000000000000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000625208 CR3: 00000001cbd63000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vsnprintf+0x13d0/0x1b60 lib/vsprintf.c:2362 snprintf+0xae/0xe0 lib/vsprintf.c:2429 print_time kernel/printk/printk.c:1226 [inline] print_prefix+0x38e/0x3f0 kernel/printk/printk.c:1251 msg_print_text+0x83/0x1d0 kernel/printk/printk.c:1274 console_unlock+0x4e6/0x1190 kernel/printk/printk.c:2388 vprintk_emit+0x391/0x990 kernel/printk/printk.c:1922 vprintk_default+0x28/0x30 kernel/printk/printk.c:1964 vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:1997 __find_get_block_slow fs/buffer.c:235 [inline] __find_get_block.cold.58+0x85/0xff fs/buffer.c:1325 __getblk_slow fs/buffer.c:1058 [inline] __getblk_gfp+0x3d3/0x1030 fs/buffer.c:1351 __bread_gfp+0x2d/0x310 fs/buffer.c:1385 sb_bread include/linux/buffer_head.h:307 [inline] __fat_write_inode+0x347/0xb60 fs/fat/inode.c:860 fat_write_inode+0x97/0x180 fs/fat/inode.c:909 write_inode fs/fs-writeback.c:1176 [inline] __writeback_single_inode+0xf4a/0x1650 fs/fs-writeback.c:1375 writeback_sb_inodes+0x71f/0x1210 fs/fs-writeback.c:1580 wb_writeback+0x480/0xfa0 fs/fs-writeback.c:1756 wb_do_writeback fs/fs-writeback.c:1901 [inline] wb_workfn+0x490/0x1780 fs/fs-writeback.c:1942 process_one_work+0xc8b/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 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: 2.423 msecs