INFO: task syz-executor.2:8076 blocked for more than 143 seconds. Not tainted 5.10.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:28736 pid: 8076 ppid: 8667 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:3779 [inline] __schedule+0x893/0x2130 kernel/sched/core.c:4528 schedule+0xcf/0x270 kernel/sched/core.c:4606 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1863 raw_release+0x58/0x890 net/can/raw.c:352 __sock_release+0xcd/0x280 net/socket.c:596 sock_close+0x18/0x20 net/socket.c:1277 __fput+0x285/0x920 fs/file_table.c:281 task_work_run+0xdd/0x190 kernel/task_work.c:151 exit_task_work include/linux/task_work.h:30 [inline] do_exit+0xb64/0x29b0 kernel/exit.c:809 do_group_exit+0x125/0x310 kernel/exit.c:906 get_signal+0x42a/0x1f10 kernel/signal.c:2758 arch_do_signal+0x82/0x2390 arch/x86/kernel/signal.c:811 exit_to_user_mode_loop kernel/entry/common.c:161 [inline] exit_to_user_mode_prepare+0x100/0x1a0 kernel/entry/common.c:191 syscall_exit_to_user_mode+0x38/0x260 kernel/entry/common.c:266 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45de79 RSP: 002b:00007f894c04dc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 0000000000000003 RBX: 0000000000000003 RCX: 000000000045de79 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 000000000169fb7f R14: 00007f894c04e9c0 R15: 000000000118bf2c Showing all locks held in the system: 3 locks held by kworker/u4:4/176: 1 lock held by khungtaskd/1647: #0: ffffffff8b3378e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8184: #0: ffff88801b0b0370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:932 2 locks held by syz-executor.2/8076: #0: ffff8881ad7b0c90 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline] #0: ffff8881ad7b0c90 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:595 #1: ffffffff8c9156d0 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1863 1 lock held by syz-executor.2/8397: #0: ffffffff8c9156d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2ac/0x5e0 net/core/net_namespace.c:479 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1647 Comm: khungtaskd Not tainted 5.10.0-rc6-syzkaller #0 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+0x107/0x163 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd43/0xfa0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 147 Comm: kworker/u4:3 Not tainted 5.10.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0x17e/0x5500 kernel/locking/lockdep.c:4735 Code: 00 00 00 fc ff df 0f b6 0c 01 48 c7 c0 20 c9 f3 8e 83 e0 07 83 c0 03 38 c8 7c 08 84 c9 0f 85 f2 13 00 00 44 8b 25 52 03 9e 0d <45> 85 e4 75 0b 83 7c 24 10 2f 0f 87 16 11 00 00 48 8d b5 18 09 00 RSP: 0018:ffffc900014bfa58 EFLAGS: 00000097 RAX: 0000000000000003 RBX: 0000000000000000 RCX: 0000000000000004 RDX: ffffffff8ebb1b80 RSI: 0000000000000000 RDI: ffffffff8b3378e8 RBP: ffff8880115f3480 R08: 0000000000000001 R09: 0000000000000000 R10: fffffbfff19d95b9 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8b3378e0 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa1b4b83000 CR3: 000000001b33d000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5437 [inline] lock_acquire+0x29d/0x740 kernel/locking/lockdep.c:5402 rcu_lock_acquire include/linux/rcupdate.h:248 [inline] rcu_read_lock include/linux/rcupdate.h:641 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline] batadv_nc_worker+0x12d/0xe50 net/batman-adv/network-coding.c:718 process_one_work+0x933/0x15a0 kernel/workqueue.c:2272 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296