INFO: task syz-executor.0:15159 blocked for more than 143 seconds. Not tainted 5.12.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:28032 pid:15159 ppid: 8405 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4322 [inline] __schedule+0x911/0x21b0 kernel/sched/core.c:5073 schedule+0xcf/0x270 kernel/sched/core.c:5152 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1407 unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1949 isotp_release+0x13b/0x690 net/can/isotp.c:1016 __sock_release+0xcd/0x280 net/socket.c:599 sock_close+0x18/0x20 net/socket.c:1258 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:140 exit_task_work include/linux/task_work.h:30 [inline] do_exit+0xbfc/0x2a60 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2150 kernel/signal.c:2781 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 RSP: 002b:00007f41ea53c188 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 0000000000000004 RBX: 000000000056c2a8 RCX: 00000000004665f9 RDX: 0000000000000006 RSI: 0000000000000002 RDI: 000000000000001d RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c2a8 R13: 00007fff6978308f R14: 00007f41ea53c300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1622: #0: ffffffff8bf74520 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6328 1 lock held by in:imklog/8095: #0: ffff888014396d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 4 locks held by kworker/u4:7/11178: #0: ffff88814079b138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88814079b138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff88814079b138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff88814079b138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff88814079b138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff88814079b138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc900017ffda8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 #2: ffffffff8d65fb90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:557 #3: ffffffff8bf7cff0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x44/0x420 kernel/rcu/tree.c:3937 2 locks held by syz-executor.0/15159: #0: ffff88803269a190 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline] #0: ffff88803269a190 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:598 #1: ffffffff8d65fb90 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1949 1 lock held by syz-executor.1/15293: #0: ffffffff8d65fb90 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:470 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1622 Comm: khungtaskd Not tainted 5.12.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 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+0xd48/0xfb0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 13643 Comm: kworker/u4:8 Not tainted 5.12.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__this_cpu_preempt_check+0x0/0x20 lib/smp_processor_id.c:69 Code: 2e 0f 1f 84 00 00 00 00 00 90 0f 1f 44 00 00 48 c7 c6 c0 2e c2 89 48 c7 c7 00 2f c2 89 e9 98 fe ff ff 0f 1f 84 00 00 00 00 00 <55> 48 89 fd 0f 1f 44 00 00 48 89 ee 5d 48 c7 c7 40 2f c2 89 e9 77 RSP: 0018:ffffc900018cfb98 EFLAGS: 00000046 RAX: 0000000000000007 RBX: 1ffff92000319f76 RCX: 0000000000000000 RDX: ffff8880122454c0 RSI: 0000000000000001 RDI: ffffffff896b97e0 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8dc613cf R10: fffffbfff1b8c279 R11: 0000000000000000 R12: 0000000000000002 R13: ffffffff8bf74520 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fece9a9b000 CR3: 0000000011bb7000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:432 [inline] lock_acquire kernel/locking/lockdep.c:5510 [inline] lock_acquire+0x170/0x740 kernel/locking/lockdep.c:5476 rcu_lock_acquire include/linux/rcupdate.h:267 [inline] rcu_read_lock include/linux/rcupdate.h:656 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:404 [inline] batadv_nc_worker+0x12d/0xe50 net/batman-adv/network-coding.c:715 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294