bridge0: port 1(bridge_slave_0) entered disabled state team0 (unregistering): Port device team_slave_1 removed team0 (unregistering): Port device team_slave_0 removed bond0 (unregistering): Releasing backup interface bond_slave_0 bond0 (unregistering): Released all slaves INFO: task syz-executor4:5262 blocked for more than 140 seconds. Not tainted 4.20.0-rc7+ #164 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D18792 5262 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xbe7/0x1700 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 fuse_lock_inode+0xba/0xf0 fs/fuse/inode.c:364 fuse_lookup+0x8f/0x3a0 fs/fuse/dir.c:350 __lookup_slow+0x2b5/0x540 fs/namei.c:1671 lookup_slow+0x57/0x80 fs/namei.c:1688 walk_component+0x92b/0x25b0 fs/namei.c:1810 link_path_walk.part.40+0xa61/0x1530 fs/namei.c:2141 link_path_walk fs/namei.c:2072 [inline] path_mountpoint+0x103/0x2180 fs/namei.c:2694 filename_mountpoint+0x245/0x460 fs/namei.c:2717 user_path_mountpoint_at+0x37/0x40 fs/namei.c:2747 ksys_umount+0x1c5/0x12d0 fs/namespace.c:1645 __do_sys_umount fs/namespace.c:1671 [inline] __se_sys_umount fs/namespace.c:1669 [inline] __x64_sys_umount+0x54/0x80 fs/namespace.c:1669 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a0b7 Code: e0 48 81 f9 00 00 20 00 77 09 48 8d 05 a2 0c 00 00 ff e0 48 81 f9 00 00 40 00 77 09 48 8d 05 60 0d 00 00 ff e0 48 81 f9 00 00 <80> 00 77 09 48 8d 05 1e 0e 00 00 ff e0 48 81 f9 00 00 00 01 77 09 RSP: 002b:00007ffcde021338 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 000000000011b40a RCX: 000000000045a0b7 RDX: 0000000000402eb0 RSI: 0000000000000002 RDI: 00007ffcde0213e0 RBP: 00000000000004b6 R08: 0000000000000000 R09: 000000000000000c R10: 0000000000000006 R11: 0000000000000206 R12: 00007ffcde022470 R13: 000000000203e940 R14: 0000000000000000 R15: 0000000000000004 Showing all locks held in the system: 1 lock held by khungtaskd/1018: #0: 00000000f9903acd (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 1 lock held by rsyslogd/5939: 2 locks held by getty/6028: #0: 000000004919187e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000b693e395 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/6029: #0: 000000001cb634ea (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000bd40059a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/6030: #0: 00000000f9fa7665 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000005088e32b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/6031: #0: 00000000af0c3011 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000046b198ca (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/6032: #0: 000000003dbc07f1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000001e9414db (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/6033: #0: 000000007e1d8c88 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000268b8a3b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/6034: #0: 000000008b4c4a52 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000777f2847 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by syz-executor4/5262: #0: 00000000417b16f7 (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:767 [inline] #0: 00000000417b16f7 (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x49/0x80 fs/namei.c:1687 #1: 0000000071813a0d (&fi->mutex){+.+.}, at: fuse_lock_inode+0xba/0xf0 fs/fuse/inode.c:364 2 locks held by syz-executor4/13399: #0: 00000000417b16f7 (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:767 [inline] #0: 00000000417b16f7 (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x49/0x80 fs/namei.c:1687 #1: 0000000071813a0d (&fi->mutex){+.+.}, at: fuse_lock_inode+0xba/0xf0 fs/fuse/inode.c:364 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1018 Comm: khungtaskd Not tainted 4.20.0-rc7+ #164 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+0x1d3/0x2c6 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:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb51/0x1060 kernel/hung_task.c:289 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57