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-executor0:4700 blocked for more than 140 seconds. b_state=0x00000029, b_size=512 Not tainted 4.18.0-rc3-next-20180706+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. device loop0 blocksize: 4096 syz-executor0 D19088 4700 1 0x00000004 __find_get_block_slow() failed. block=1, b_blocknr=8 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 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+0xfb/0x450 kernel/sched/core.c:3545 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 wb_wait_for_completion+0x201/0x2e0 fs/fs-writeback.c:221 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 writeback_inodes_sb_nr fs/fs-writeback.c:2350 [inline] writeback_inodes_sb+0x27/0x30 fs/fs-writeback.c:2365 device loop0 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 loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 generic_shutdown_super+0xdd/0x530 fs/super.c:441 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __find_get_block_slow() failed. block=1, b_blocknr=8 kill_block_super+0xa4/0x100 fs/super.c:1379 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 deactivate_locked_super+0x97/0x100 fs/super.c:328 deactivate_super+0x2bb/0x320 fs/super.c:359 __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:1044 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 __cleanup_mnt+0x16/0x20 fs/namespace.c:1051 task_work_run+0x1ec/0x2a0 kernel/task_work.c:113 __find_get_block_slow() failed. block=1, b_blocknr=8 b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 tracehook_notify_resume include/linux/tracehook.h:192 [inline] exit_to_usermode_loop+0x313/0x370 arch/x86/entry/common.c:166 __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 loop0 blocksize: 4096 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4585b7 __find_get_block_slow() failed. block=1, b_blocknr=8 Code: Bad RIP value. b_state=0x00000029, b_size=512 device loop0 blocksize: 4096 RSP: 002b:00007ffde31052d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000004585b7 RDX: 0000000001b98a33 RSI: 0000000000000002 RDI: 00007ffde3106440 __find_get_block_slow() failed. block=1, b_blocknr=8 RBP: 00007ffde3106440 R08: 0000000000000000 R09: 000000000000000b R10: 0000000000000005 R11: 0000000000000246 R12: 0000000001b98940 R13: 0000000000000000 R14: 00007ffde3107b20 R15: 0000000000702140 b_state=0x00000029, b_size=512 INFO: lockdep is turned off. device loop0 blocksize: 4096 NMI backtrace for cpu 0 CPU: 0 PID: 897 Comm: khungtaskd Not tainted 4.18.0-rc3-next-20180706+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 __find_get_block_slow() failed. block=1, b_blocknr=8 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.5+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62 device loop0 blocksize: 4096 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:143 [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 loop0 blocksize: 4096 kthread+0x345/0x410 kernel/kthread.c:246 __find_get_block_slow() failed. block=1, b_blocknr=8 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: b_state=0x00000029, b_size=512 NMI backtrace for cpu 1 CPU: 1 PID: 58 Comm: kworker/u4:2 Not tainted 4.18.0-rc3-next-20180706+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:write_comp_data+0x0/0x70 Code: fd ff ff 48 8b bd d0 fe ff ff e8 6b 6f 3e 00 e9 ad fc ff ff 4c 89 ef e8 be 6e 3e 00 e9 76 fc ff ff e8 d4 ce ca ff 90 90 90 90 <55> 65 4c 8b 04 25 40 ee 01 00 65 8b 05 cf 73 85 7e 48 89 e5 a9 00 RSP: 0018:ffff8801daf07918 EFLAGS: 00000006 RAX: 0000000000000240 RBX: 0000000000000101 RCX: ffffffff8169d23d RDX: 0000000000000240 RSI: 0000000000000240 RDI: 0000000000000004 RBP: ffff8801daf07920 R08: ffff8801d9654740 R09: ffffed003b5e4938 R10: ffffed003b5e4938 R11: ffff8801daf249c3 R12: 0000000000000008 R13: 0000000000000201 R14: 0000000000000240 R15: 0000000000000240 FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001bb7d5000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: next_pending_bucket kernel/time/timer.c:1407 [inline] __next_timer_interrupt+0x12d/0x1a0 kernel/time/timer.c:1426 collect_expired_timers kernel/time/timer.c:1599 [inline] __run_timers+0x24b/0xc70 kernel/time/timer.c:1662 run_timer_softirq+0x60/0x70 kernel/time/timer.c:1694 __do_softirq+0x2e8/0xb17 kernel/softirq.c:288 invoke_softirq kernel/softirq.c:368 [inline] irq_exit+0x1d1/0x200 kernel/softirq.c:408 exiting_irq arch/x86/include/asm/apic.h:527 [inline] smp_apic_timer_interrupt+0x186/0x730 arch/x86/kernel/apic/apic.c:1052 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:867 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:783 [inline] RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1678 [inline] RIP: 0010:vprintk_emit+0xbe9/0xdf0 kernel/printk/printk.c:1906 Code: fc ff df 41 80 3c 04 00 0f 85 d4 01 00 00 48 83 3d 53 98 8e 07 00 0f 84 fe 00 00 00 e8 40 60 19 00 48 8b bd a8 fe ff ff 57 9d <0f> 1f 44 00 00 e9 18 fe ff ff 41 80 fd 64 0f 84 eb f9 ff ff e9 ef RSP: 0018:ffff8801d965e0e8 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffff8801d9654740 RBX: 0000000000000200 RCX: ffffffff816317fe RDX: 0000000000000000 RSI: ffffffff81631a20 RDI: 0000000000000293 RBP: ffff8801d965e278 R08: ffff8801d9654740 R09: 0000000000000001 R10: fffffbfff11f1224 R11: ffffffff88f89123 R12: 1ffffffff11e364d R13: 000000000000001e R14: ffffed003b2cbc3a R15: ffffffff8aa123a0 vprintk_default+0x28/0x30 kernel/printk/printk.c:1948 vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382 printk+0xa7/0xcf kernel/printk/printk.c:1981 __find_get_block_slow fs/buffer.c:236 [inline] __find_get_block.cold.61+0x85/0x103 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:856 fat_write_inode+0x97/0x180 fs/fat/inode.c:905 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 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.328 msecs