RDX: 0000000000000001 RSI: 0000000020000100 RDI: 0000000000000004 RBP: 00007f03ccf811d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc3d2e087f R14: 00007f03ccf81300 R15: 0000000000022000 INFO: task syz-executor.5:10567 blocked for more than 140 seconds. Not tainted 4.14.229-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28936 10567 11481 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 wb_wait_for_completion fs/fs-writeback.c:222 [inline] wb_wait_for_completion+0x118/0x170 fs/fs-writeback.c:218 sync_inodes_sb+0x173/0x880 fs/fs-writeback.c:2464 __sync_filesystem fs/sync.c:34 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x12f/0x230 fs/sync.c:48 nilfs_remount+0x51/0x470 fs/nilfs2/super.c:1129 do_remount_sb+0x150/0x530 fs/super.c:868 do_remount fs/namespace.c:2370 [inline] do_mount+0x1632/0x2a00 fs/namespace.c:2870 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x46797a RSP: 002b:00007ff030db0fa8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000046797a RDX: 0000000020000540 RSI: 0000000020000400 RDI: 0000000000000000 RBP: 00007ff030db1040 R08: 00007ff030db1040 R09: 0000000020000540 R10: 000000000024002f R11: 0000000000000202 R12: 0000000020000540 R13: 0000000020000400 R14: 00007ff030db1000 R15: 0000000020000480 Showing all locks held in the system: 2 locks held by kworker/u4:3/1152: #0: ("writeback"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&(&wb->dwork)->work)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 1 lock held by khungtaskd/1533: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 2 locks held by syz-executor.5/10567: #0: (&type->s_umount_key#101){++++}, at: [] do_remount fs/namespace.c:2364 [inline] #0: (&type->s_umount_key#101){++++}, at: [] do_mount+0x837/0x2a00 fs/namespace.c:2870 #1: (&bdi->wb_switch_rwsem){+.+.}, at: [] bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline] #1: (&bdi->wb_switch_rwsem){+.+.}, at: [] sync_inodes_sb+0x156/0x880 fs/fs-writeback.c:2462 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1533 Comm: khungtaskd Not tainted 4.14.229-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.229-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker task: ffff8880b5ff2140 task.stack: ffff8880b5ff8000 RIP: 0010:__lock_release kernel/locking/lockdep.c:3795 [inline] RIP: 0010:lock_release+0x319/0x870 kernel/locking/lockdep.c:4017 RSP: 0018:ffff8880b5fffc48 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 1ffff11016bfff8c RCX: ffff8880b5ff2a18 RDX: ffff8880b5ff2a18 RSI: ffffffff88f77800 RDI: ffff8880b5ff2a3a RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: ffff8880b5ff2140 R12: ffffffff86e9ebf0 R13: ffffffff8bebbd40 R14: ffff8880b5ff2140 R15: 0000000000000003 FS: 0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa871a33000 CR3: 00000000a21cf000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release include/linux/rcupdate.h:247 [inline] rcu_read_unlock include/linux/rcupdate.h:685 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:420 [inline] batadv_nc_worker+0x5a7/0xc50 net/batman-adv/network-coding.c:726 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: 00 fc ff df 48 8b 4c 24 08 8b 6c 24 38 48 c1 e9 03 0f b6 04 01 84 c0 74 08 3c 03 0f 8e c6 04 00 00 48 89 d1 41 89 ae 80 08 00 00 <48> b8 00 00 00 00 00 fc ff df 48 c1 e9 03 80 3c 01 00 0f 85 bd