INFO: task syz-executor.0:1465 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29920 1465 8116 0x00000004 device bond193 entered promiscuous mode Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 device veth1345 entered promiscuous mode __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x20a/0x390 kernel/locking/rwsem-xadd.c:309 bond193: Enslaving veth1345 as an active interface with an up link call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x44/0x80 kernel/locking/rwsem.c:26 iterate_supers+0xdb/0x290 fs/super.c:631 ksys_sync+0x86/0x150 fs/sync.c:113 __ia32_sys_sync+0xa/0x10 fs/sync.c:124 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f9e8b4780c9 Code: Bad RIP value. RSP: 002b:00007f9e899ea168 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f9e8b597f80 RCX: 00007f9e8b4780c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f9e8b4d3ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe36cd889f R14: 00007f9e899ea300 R15: 0000000000022000 bond193 (unregistering): Releasing backup interface veth1345 Showing all locks held in the system: 1 lock held by khungtaskd/1570: device veth1345 left promiscuous mode #0: 000000003c155214 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7800: #0: 000000006f3ad315 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 3 locks held by kworker/1:3/9315: #0: 00000000cb7f79ae ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 00000000cef921ce ((linkwatch_work).work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 00000000ec3e2d6e (rtnl_mutex){+.+.}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:236 2 locks held by kworker/1:2/4136: #0: 00000000cf292975 ((wq_completion)"rcu_gp"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 0000000058b56059 ((work_completion)(&rew.rew_work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 5 locks held by syz-executor.4/14005: 1 lock held by syz-executor.0/1465: #0: 000000000153d3d6 (&type->s_umount_key#47){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631 2 locks held by syz-executor.5/16919: #0: 00000000ec3e2d6e (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000ec3e2d6e (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4779 #1: 00000000d941f852 (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #1: 00000000d941f852 (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x4dc/0x6f0 kernel/rcu/tree_exp.h:667 1 lock held by syz-executor.1/16947: #0: 00000000ec3e2d6e (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000ec3e2d6e (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4779 1 lock held by syz-executor.2/17028: #0: 00000000ec3e2d6e (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000ec3e2d6e (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4779 3 locks held by syz-executor.0/17055: #0: 000000000bd4d831 (&tty->legacy_mutex){+.+.}, at: tty_lock+0x6a/0xa0 drivers/tty/tty_mutex.c:19 #1: 00000000a4f996b6 (&tty->ldisc_sem){++++}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:320 [inline] #1: 00000000a4f996b6 (&tty->ldisc_sem){++++}, at: tty_ldisc_lock+0x4d/0x90 drivers/tty/tty_ldisc.c:344 #2: 00000000ec3e2d6e (rtnl_mutex){+.+.}, at: register_netdev+0x11/0x50 net/core/dev.c:8857 1 lock held by syz-executor.0/17060: #0: 00000000a4f996b6 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 bond193 (unregistering): Released all slaves ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60