__find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 INFO: task syz-executor6:4488 blocked for more than 140 seconds. device loop6 blocksize: 4096 Not tainted 4.18.0-rc5-next-20180717+ #9 __find_get_block_slow() failed. block=1, b_blocknr=8 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor6 D b_state=0x00000029, b_size=512 21232 4488 1 0x00000004 device loop6 blocksize: 4096 Call Trace: context_switch kernel/sched/core.c:2821 [inline] __schedule+0x87c/0x1ea0 kernel/sched/core.c:3469 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 schedule+0xfb/0x450 kernel/sched/core.c:3513 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 wb_wait_for_completion+0x201/0x2e0 fs/fs-writeback.c:221 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 __writeback_inodes_sb_nr+0x405/0x580 fs/fs-writeback.c:2333 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 writeback_inodes_sb_nr fs/fs-writeback.c:2350 [inline] writeback_inodes_sb+0x27/0x30 fs/fs-writeback.c:2365 device loop6 blocksize: 4096 __sync_filesystem fs/sync.c:36 [inline] sync_filesystem+0x16f/0x330 fs/sync.c:64 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 generic_shutdown_super+0xdd/0x530 fs/super.c:441 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 kill_block_super+0xa4/0x100 fs/super.c:1371 __find_get_block_slow() failed. block=1, b_blocknr=8 deactivate_locked_super+0x97/0x100 fs/super.c:328 deactivate_super+0x2bb/0x320 fs/super.c:359 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 cleanup_mnt+0xbf/0x160 fs/namespace.c:1044 __find_get_block_slow() failed. block=1, b_blocknr=8 __cleanup_mnt+0x16/0x20 fs/namespace.c:1051 task_work_run+0x1ec/0x2a0 kernel/task_work.c:113 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 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 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 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 loop6 blocksize: 4096 RIP: 0033:0x4584c7 __find_get_block_slow() failed. block=1, b_blocknr=8 Code: Bad RIP value. b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 RSP: 002b:00007ffee84b2078 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 __find_get_block_slow() failed. block=1, b_blocknr=8 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000004584c7 RDX: 0000000000402738 RSI: 0000000000000002 RDI: 00007ffee84b2110 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 RBP: 00007ffee84b3e20 R08: 0000000000000000 R09: 000000000000000b __find_get_block_slow() failed. block=1, b_blocknr=8 R10: 0000000000000005 R11: 0000000000000202 R12: 0000000002559940 R13: 0000000000000000 R14: 00007ffee84b37f0 R15: 0000000000702140 b_state=0x00000029, b_size=512 INFO: lockdep is turned off. device loop6 blocksize: 4096 NMI backtrace for cpu 0 CPU: 0 PID: 902 Comm: khungtaskd Not tainted 4.18.0-rc5-next-20180717+ #9 __find_get_block_slow() failed. block=1, b_blocknr=8 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+0x1c9/0x2b4 lib/dump_stack.c:113 b_state=0x00000029, b_size=512 nmi_cpu_backtrace.cold.3+0x48/0x88 lib/nmi_backtrace.c:101 device loop6 blocksize: 4096 nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb39/0x10b0 kernel/hung_task.c:265 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop6 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 b_state=0x00000029, b_size=512 Sending NMI from CPU 0 to CPUs 1: device loop6 blocksize: 4096 NMI backtrace for cpu 1 CPU: 1 PID: 22 Comm: kworker/u4:1 Not tainted 4.18.0-rc5-next-20180717+ #9 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:6) RIP: 0010:__write_once_size include/linux/compiler.h:215 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x4b/0x50 kernel/kcov.c:109 Code: 90 98 12 00 00 83 fa 02 75 20 48 8b 88 a0 12 00 00 8b 80 9c 12 00 00 48 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 <5d> c3 0f 1f 00 55 40 0f b6 d6 40 0f b6 f7 31 ff 48 89 e5 48 8b 4d RSP: 0018:ffff8801d9455bb0 EFLAGS: 00000093 RAX: ffff8801d943e5c0 RBX: ffff8801d9455cd8 RCX: ffffffff87997a5d RDX: 0000000000000000 RSI: ffffffff87997c2d RDI: 0000000000000007 RBP: ffff8801d9455bb0 R08: ffff8801d943e5c0 R09: fffffbfff11f1258 R10: fffffbfff11f1258 R11: ffffffff88f892c3 R12: 0000000000003331 R13: 0000000000000004 R14: 000000000000000a R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001b3a9c000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: put_dec_trunc8+0x28d/0x300 lib/vsprintf.c:193 put_dec+0x3b/0xf0 lib/vsprintf.c:258 number+0xb94/0xc90 lib/vsprintf.c:467 vsnprintf+0x13d6/0x1b60 lib/vsprintf.c:2358 snprintf+0xae/0xe0 lib/vsprintf.c:2425 print_time kernel/printk/printk.c:1221 [inline] print_prefix+0x38e/0x3f0 kernel/printk/printk.c:1246 msg_print_text+0x85/0x1c0 kernel/printk/printk.c:1269 console_unlock+0x71c/0x1110 kernel/printk/printk.c:2379 vprintk_emit+0x33a/0x910 kernel/printk/printk.c:1924 vprintk_default+0x28/0x30 kernel/printk/printk.c:1965 vprintk_func+0x7a/0x117 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:1998 __find_get_block_slow fs/buffer.c:238 [inline] __find_get_block.cold.61+0xd8/0xff fs/buffer.c:1295 __getblk_slow fs/buffer.c:1040 [inline] __getblk_gfp+0x2be/0xb10 fs/buffer.c:1321 __bread_gfp+0x2d/0x310 fs/buffer.c:1355 sb_bread include/linux/buffer_head.h:307 [inline] __fat_write_inode+0x347/0xb60 fs/fat/inode.c:864 fat_write_inode+0x97/0x180 fs/fat/inode.c:913 write_inode fs/fs-writeback.c:1176 [inline] __writeback_single_inode+0xf6a/0x1620 fs/fs-writeback.c:1375 writeback_sb_inodes+0x71f/0x1220 fs/fs-writeback.c:1580 wb_writeback+0x470/0xf80 fs/fs-writeback.c:1756 wb_do_writeback fs/fs-writeback.c:1901 [inline] wb_workfn+0x477/0x1760 fs/fs-writeback.c:1942 process_one_work+0xc73/0x1ba0 kernel/workqueue.c:2153 worker_thread+0x189/0x13c0 kernel/workqueue.c:2296 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415