INFO: task syz-executor.1:31107 blocked for more than 143 seconds. Not tainted 5.13.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:25080 pid:31107 ppid: 22322 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:4339 [inline] __schedule+0xb98/0x1120 kernel/sched/core.c:5147 schedule+0x14b/0x200 kernel/sched/core.c:5226 rwsem_down_write_slowpath+0xe52/0x1590 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x165/0x170 kernel/locking/rwsem.c:1407 unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949 isotp_release+0x244/0x6e0 net/can/isotp.c:1016 __sock_release net/socket.c:599 [inline] sock_close+0xd8/0x260 net/socket.c:1258 __fput+0x352/0x7b0 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0x736/0x23d0 kernel/exit.c:826 do_group_exit+0x168/0x2d0 kernel/exit.c:923 get_signal+0x1770/0x2180 kernel/signal.c:2835 arch_do_signal_or_restart+0x8e/0x6c0 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+0xac/0x200 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301 do_syscall_64+0x4b/0xb0 arch/x86/entry/common.c:57 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665d9 RSP: 002b:00007eff71029188 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 0000000000000004 RBX: 000000000056c038 RCX: 00000000004665d9 RDX: 0000000000000006 RSI: 0000000000000002 RDI: 000000000000001d RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007ffc73c11aff R14: 00007eff71029300 R15: 0000000000022000 Showing all locks held in the system: 4 locks held by kworker/u4:3/140: #0: ffff888016993138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7aa/0x10c0 kernel/workqueue.c:2249 #1: ffffc9000145fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7e8/0x10c0 kernel/workqueue.c:2251 #2: ffffffff8df1f430 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf0/0xc60 net/core/net_namespace.c:557 #3: ffffffff8cf1a2f0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x9c/0x530 kernel/rcu/tree.c:4018 1 lock held by khungtaskd/1633: #0: ffffffff8cf15c40 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 arch/x86/pci/mmconfig_64.c:151 1 lock held by in:imklog/8104: #0: ffff88802257aff0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:974 2 locks held by agetty/8132: #0: ffff8880295dc098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc90000f8c2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6c3/0x1cf0 drivers/tty/n_tty.c:2179 2 locks held by syz-executor.1/31107: #0: ffff88807e6fa6d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline] #0: ffff88807e6fa6d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release net/socket.c:598 [inline] #0: ffff88807e6fa6d0 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: sock_close+0x94/0x260 net/socket.c:1258 #1: ffffffff8df1f430 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x8e/0x430 net/core/dev.c:1949 1 lock held by syz-executor.1/31428: #0: ffffffff8df1f430 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x378/0x5e0 net/core/net_namespace.c:470 1 lock held by syz-executor.0/31430: #0: ffffffff8df1f430 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x378/0x5e0 net/core/net_namespace.c:470 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1633 Comm: khungtaskd Not tainted 5.13.0-rc3-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+0x202/0x31e lib/dump_stack.c:120 nmi_cpu_backtrace+0x16c/0x190 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x191/0x2f0 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+0xcfb/0xd40 kernel/hung_task.c:294 kthread+0x39a/0x3c0 kernel/kthread.c:313 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: 4843 Comm: systemd-journal Not tainted 5.13.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rcu_read_lock_sched_held+0xb1/0x110 kernel/rcu/update.c:126 Code: 85 c0 74 34 41 bf 01 00 00 00 48 c7 04 24 0e 36 e0 45 49 c7 04 1e 00 00 00 00 65 48 8b 04 25 28 00 00 00 48 3b 44 24 50 75 4d <44> 89 f8 48 8d 65 e8 5b 41 5e 41 5f 5d c3 65 8b 05 12 90 98 7e 41 RSP: 0018:ffffc9000a337c00 EFLAGS: 00000046 RAX: c28535e45e7e3400 RBX: 1ffff92001466f80 RCX: 0000000080000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000a337c88 R08: dffffc0000000000 R09: fffffbfff1c7047e R10: fffffbfff1c7047e R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000001 FS: 00007f8c02c9f8c0(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8c0037a000 CR3: 0000000012cbf000 CR4: 00000000001526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: trace_lock_acquire+0x6b/0x180 include/trace/events/lock.h:13 lock_acquire+0xa9/0x720 kernel/locking/lockdep.c:5483 do_write_seqcount_begin_nested include/linux/seqlock.h:520 [inline] do_write_seqcount_begin include/linux/seqlock.h:545 [inline] vtime_user_exit+0xb9/0x3e0 kernel/sched/cputime.c:719 __context_tracking_exit+0x7a/0xd0 kernel/context_tracking.c:160 user_exit_irqoff include/linux/context_tracking.h:47 [inline] __enter_from_user_mode kernel/entry/common.c:21 [inline] syscall_enter_from_user_mode+0x19c/0x1c0 kernel/entry/common.c:103 do_syscall_64+0x21/0xb0 arch/x86/entry/common.c:42 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f8c0222e210 Code: 73 01 c3 48 8b 0d 98 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 c1 20 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 4e fc ff ff 48 89 04 24 RSP: 002b:00007ffd7a08e948 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007ffd7a0913c0 RCX: 00007f8c0222e210 RDX: 0000000000002000 RSI: 00007ffd7a08f1c0 RDI: 0000000000000009 RBP: 0000000000000000 R08: 0000000000000008 R09: 0000000000000070 R10: 00007ffd7a1e4118 R11: 0000000000000246 R12: 00007ffd7a08f1c0 R13: 00007ffd7a091318 R14: 0000564d92d0d958 R15: 0005c3510ca43e26