kworker/u4:6(13358): getblk(): executed=9 bh_count=0 bh_state=0 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 INFO: task syz-executor3:6996 blocked for more than 140 seconds. b_state=0x00000029, b_size=512 Not tainted 4.18.0-rc7-next-20180801+ #29 device loop3 blocksize: 4096 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. __find_get_block_slow() failed. block=3, b_blocknr=24 syz-executor3 D21584 6996 1 0x00000004 b_state=0x00000029, b_size=512 Call Trace: device loop3 blocksize: 4096 context_switch kernel/sched/core.c:2823 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3471 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 schedule+0xfb/0x450 kernel/sched/core.c:3515 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 wb_wait_for_completion+0x201/0x2e0 fs/fs-writeback.c:221 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __writeback_inodes_sb_nr+0x405/0x580 fs/fs-writeback.c:2333 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 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=3, b_blocknr=24 __sync_filesystem fs/sync.c:36 [inline] sync_filesystem+0x16f/0x330 fs/sync.c:64 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 generic_shutdown_super+0xdd/0x530 fs/super.c:441 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 kill_block_super+0xa4/0x100 fs/super.c:1371 deactivate_locked_super+0x97/0x100 fs/super.c:328 device loop3 blocksize: 4096 deactivate_super+0x2bb/0x320 fs/super.c:359 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 cleanup_mnt+0xbf/0x160 fs/namespace.c:1041 __cleanup_mnt+0x16/0x20 fs/namespace.c:1048 __find_get_block_slow() failed. block=3, b_blocknr=24 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 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 loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 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=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 b_state=0x00000029, b_size=512 entry_SYSCALL_64_after_hwframe+0x49/0xbe device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 RIP: 0033:0x459417 Code: Bad RIP value. b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 RSP: 002b:00007ffc4be1d588 EFLAGS: 00000206 __find_get_block_slow() failed. block=3, b_blocknr=24 ORIG_RAX: 00000000000000a6 b_state=0x00000029, b_size=512 RAX: 0000000000000000 RBX: 00000000000956fb RCX: 0000000000459417 device loop3 blocksize: 4096 RDX: 0000000000408568 RSI: 0000000000000002 RDI: 00007ffc4be1d620 __find_get_block_slow() failed. block=3, b_blocknr=24 RBP: 00007ffc4be1e670 R08: 0000000000000000 R09: 000000000000000b b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 R10: 0000000000000005 R11: 0000000000000206 R12: 0000000000a51940 __find_get_block_slow() failed. block=3, b_blocknr=24 R13: 0000000000000000 R14: 0000000000000182 R15: badc0ffeebadface b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 INFO: lockdep is turned off. __find_get_block_slow() failed. block=3, b_blocknr=24 NMI backtrace for cpu 0 b_state=0x00000029, b_size=512 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 CPU: 0 PID: 774 Comm: khungtaskd Not tainted 4.18.0-rc7-next-20180801+ #29 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+0x1c9/0x2b4 lib/dump_stack.c:113 device loop3 blocksize: 4096 nmi_cpu_backtrace.cold.3+0x48/0x88 lib/nmi_backtrace.c:101 __find_get_block_slow() failed. block=3, b_blocknr=24 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 b_state=0x00000029, b_size=512 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 device loop3 blocksize: 4096 __find_get_block_slow() failed. block=3, b_blocknr=24 kthread+0x35a/0x420 kernel/kthread.c:246 b_state=0x00000029, b_size=512 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: device loop3 blocksize: 4096 NMI backtrace for cpu 1 CPU: 1 PID: 13358 Comm: kworker/u4:6 Not tainted 4.18.0-rc7-next-20180801+ #29 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:3) RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:146 Code: 14 dd 28 00 00 00 4d 39 d0 72 1b 49 83 c1 01 4a 89 7c 10 e0 4a 89 74 10 e8 4a 89 54 10 f0 4a 89 4c d8 20 4c 89 08 5d c3 66 90 <55> 65 48 8b 04 25 40 ee 01 00 65 8b 15 0f 52 85 7e 48 89 e5 81 e2 RSP: 0018:ffff88018e1c5b78 EFLAGS: 00000086 RAX: ffff8801bb566280 RBX: ffff88018e1c5c9a RCX: ffffffff86b3287d RDX: 0000000000000000 RSI: ffffffff86b32a4d RDI: 0000000000000007 RBP: ffff88018e1c5ba0 R08: ffff8801bb566280 R09: fffffbfff0ff1238 R10: fffffbfff0ff1238 R11: ffffffff87f891c3 R12: 0000000000000008 R13: 0000000000000008 R14: 000000000000000a R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f67d2621000 CR3: 00000001c816d000 CR4: 00000000001406e0 Call Trace: 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:1224 [inline] print_prefix+0x38e/0x3f0 kernel/printk/printk.c:1249 msg_print_text+0x85/0x1c0 kernel/printk/printk.c:1272 console_unlock+0x71c/0x1110 kernel/printk/printk.c:2382 vprintk_emit+0x33a/0x910 kernel/printk/printk.c:1927 vprintk_default+0x28/0x30 kernel/printk/printk.c:1968 vprintk_func+0x7a/0x117 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:2001 __find_get_block_slow fs/buffer.c:238 [inline] __find_get_block.cold.61+0xd8/0xff fs/buffer.c:1326 __getblk_slow fs/buffer.c:1059 [inline] __getblk_gfp+0x3dc/0xe00 fs/buffer.c:1352 __bread_gfp+0x2d/0x310 fs/buffer.c:1386 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+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415