INFO: task syz-executor.3:22743 blocked for more than 143 seconds. Not tainted 5.12.0-rc6-next-20210409-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:27968 pid:22743 ppid: 8424 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:4329 [inline] __schedule+0x917/0x2170 kernel/sched/core.c:5079 schedule+0xcf/0x270 kernel/sched/core.c:5158 rwsem_down_write_slowpath+0x7dc/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:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xbfc/0x2a70 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2150 kernel/signal.c:2779 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: 0033:0x466459 RSP: 002b:00007fcb02938188 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 0000000000000004 RBX: 000000000056c008 RCX: 0000000000466459 RDX: 0000000000000006 RSI: 0000000000000002 RDI: 000000000000001d RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007ffc2f11618f R14: 00007fcb02938300 R15: 0000000000022000 Showing all locks held in the system: 3 locks held by kworker/u4:0/9: #0: ffff888011cab138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888011cab138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888011cab138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888011cab138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888011cab138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888011cab138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc90000ce7da8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 #2: ffffffff8d67de10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:557 1 lock held by khungtaskd/1650: #0: ffffffff8bf752a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6333 2 locks held by in:imklog/8128: #0: ffff8880127579f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 #1: ffffffff8bf752a0 (rcu_read_lock){....}-{1:2}, at: double_lock_hb kernel/futex.c:1574 [inline] #1: ffffffff8bf752a0 (rcu_read_lock){....}-{1:2}, at: double_lock_hb kernel/futex.c:1569 [inline] #1: ffffffff8bf752a0 (rcu_read_lock){....}-{1:2}, at: futex_wake_op kernel/futex.c:1710 [inline] #1: ffffffff8bf752a0 (rcu_read_lock){....}-{1:2}, at: do_futex+0xb37/0x1780 kernel/futex.c:3744 2 locks held by syz-executor.3/22743: #0: ffff888034f56190 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline] #0: ffff888034f56190 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:598 #1: ffffffff8d67de10 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1949 1 lock held by syz-executor.2/22876: #0: ffffffff8d67de10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:470 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1650 Comm: khungtaskd Not tainted 5.12.0-rc6-next-20210409-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:253 [inline] watchdog+0xd3b/0xf50 kernel/hung_task.c:338 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: 28 Comm: kworker/u4:2 Not tainted 5.12.0-rc6-next-20210409-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: phy3 ieee80211_iface_work RIP: 0010:get_running_cputimer include/linux/sched/cputime.h:87 [inline] RIP: 0010:account_group_exec_runtime include/linux/sched/cputime.h:172 [inline] RIP: 0010:update_curr+0x40c/0x850 kernel/sched/fair.c:856 Code: 00 48 8d bb 68 07 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 db 03 00 00 4c 8b ab 68 07 00 00 <48> b8 00 00 00 00 00 fc ff df 49 8d bd 90 01 00 00 4d 8d b5 30 01 RSP: 0018:ffffc90000e3fab8 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff888011d139c0 RCX: ffffc90000e3fa40 RDX: 1ffff110023a2825 RSI: 0000000000000004 RDI: ffff888011d14128 RBP: ffff8880b9c353c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 00000000000060bb R13: ffff888011c92080 R14: ffff888011d13900 R15: ffff88801c151d40 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe1d2a5e000 CR3: 00000000290f8000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: enqueue_entity+0x244/0x2090 kernel/sched/fair.c:4222 enqueue_task_fair+0x1d8/0x1a90 kernel/sched/fair.c:5527 enqueue_task kernel/sched/core.c:1594 [inline] activate_task kernel/sched/core.c:1613 [inline] ttwu_do_activate+0x185/0x660 kernel/sched/core.c:2998 ttwu_queue kernel/sched/core.c:3195 [inline] try_to_wake_up+0x62e/0x1590 kernel/sched/core.c:3473 wake_up_worker kernel/workqueue.c:837 [inline] process_one_work+0x7aa/0x1600 kernel/workqueue.c:2238 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