kworker/u4:1(7419): getblk(): executed=9 bh_count=0 bh_state=0 kworker/u4:1(7419): getblk(): executed=9 bh_count=0 bh_state=0 kworker/u4:1(7419): getblk(): executed=9 bh_count=0 bh_state=0 kworker/u4:1(7419): getblk(): executed=9 bh_count=0 bh_state=0 kworker/u4:1(7419): getblk(): executed=9 bh_count=0 bh_state=0 INFO: task syz-executor4:11198 blocked for more than 140 seconds. Not tainted 4.19.0-rc6-next-20181004+ #87 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D24488 11198 6160 0x00000004 Call Trace: context_switch kernel/sched/core.c:2830 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3479 schedule+0xfe/0x460 kernel/sched/core.c:3523 wb_wait_for_completion+0x1f9/0x2d0 fs/fs-writeback.c:221 sync_inodes_sb+0x33e/0x480 fs/fs-writeback.c:2417 sync_inodes_one_sb+0x59/0x70 fs/sync.c:74 iterate_supers+0x149/0x290 fs/super.c:724 ksys_sync+0xec/0x1e0 fs/sync.c:113 __ia32_sys_sync+0xe/0x20 fs/sync.c:124 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 kworker/u4:1(7419): getblk(): executed=9 bh_count=0 bh_state=0 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457579 Code: Bad RIP value. RSP: 002b:00007f10e8c03c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 000000000072bf08 RCX: 0000000000457579 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f10e8c046d4 R13: 00000000004c2ec2 R14: 00000000004d7ad0 R15: 00000000ffffffff INFO: task syz-executor4:11203 blocked for more than 140 seconds. Not tainted 4.19.0-rc6-next-20181004+ #87 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D23200 11203 6160 0x00000004 Call Trace: context_switch kernel/sched/core.c:2830 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3479 schedule+0xfe/0x460 kernel/sched/core.c:3523 wb_wait_for_completion+0x1f9/0x2d0 fs/fs-writeback.c:221 sync_inodes_sb+0x33e/0x480 fs/fs-writeback.c:2417 sync_inodes_one_sb+0x59/0x70 fs/sync.c:74 iterate_supers+0x149/0x290 fs/super.c:724 ksys_sync+0xec/0x1e0 fs/sync.c:113 __ia32_sys_sync+0xe/0x20 fs/sync.c:124 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457579 Code: Bad RIP value. RSP: 002b:00007f10e8be2c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 000000000072bfa8 RCX: 0000000000457579 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f10e8be36d4 R13: 00000000004c2ec2 R14: 00000000004d7ad0 R15: 00000000ffffffff INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 PID: 980 Comm: khungtaskd Not tainted 4.19.0-rc6-next-20181004+ #87 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+0x1d3/0x2c4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1c2/0x22c 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+0xb39/0x1050 kernel/hung_task.c:265 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.003 msecs NMI backtrace for cpu 1 CPU: 1 PID: 7419 Comm: kworker/u4:1 Not tainted 4.19.0-rc6-next-20181004+ #87 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:lookup_bh_lru fs/buffer.c:1294 [inline] RIP: 0010:__find_get_block+0x1b0/0xf10 fs/buffer.c:1321 Code: e0 92 02 00 65 4a 8b 1c f0 48 85 db 48 89 9d 90 fe ff ff 74 b4 e8 10 be 9d ff 48 8d 7b 18 48 89 f8 48 c1 e8 03 42 80 3c 28 00 <0f> 85 a4 0b 00 00 4c 8b 7b 18 48 8b bd b0 fe ff ff 4c 89 fe e8 97 RSP: 0018:ffff8801885ae1b8 EFLAGS: 00000046 RAX: 1ffff100371ebec0 RBX: ffff8801b8f5f5e8 RCX: ffffffff838fd66d RDX: 0000000000000000 RSI: ffffffff81dfbd00 RDI: ffff8801b8f5f600 RBP: ffff8801885ae348 R08: ffff8801b95d4200 R09: fffff94000d9c156 R10: fffff94000d9c156 R11: ffffea0006ce0ab7 R12: 0000000000000006 R13: dffffc0000000000 R14: 0000000000000006 R15: 000000000003045e FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001bdf57000 CR4: 00000000001406e0 Call Trace: __getblk_slow fs/buffer.c:1058 [inline] __getblk_gfp+0x3d3/0x1030 fs/buffer.c:1351 __bread_gfp+0x2d/0x300 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 __writeback_inodes_wb+0x1b9/0x340 fs/fs-writeback.c:1649 wb_writeback+0xa64/0xfb0 fs/fs-writeback.c:1758 wb_check_background_flush fs/fs-writeback.c:1826 [inline] wb_do_writeback fs/fs-writeback.c:1914 [inline] wb_workfn+0xd5b/0x1780 fs/fs-writeback.c:1942 process_one_work+0xc8b/0x1b80 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