INFO: task kworker/u8:0:4234 blocked for more than 430 seconds. Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:0 pid:4234 tgid:4234 ppid:2 flags:0x00000008 Workqueue: netns cleanup_net Call trace: __switch_to+0x204/0x39c arch/arm64/kernel/process.c:606 context_switch kernel/sched/core.c:5328 [inline] __schedule+0xafc/0x2df4 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xd0/0x304 kernel/sched/core.c:6782 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6839 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x4e8/0x840 kernel/locking/mutex.c:752 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:804 rcu_barrier+0x4c/0x594 kernel/rcu/tree.c:4562 netdev_run_todo+0x250/0xd04 net/core/dev.c:10782 rtnl_unlock+0x10/0x1c net/core/rtnetlink.c:152 default_device_exit_batch+0x558/0x770 net/core/dev.c:11949 ops_exit_list+0xf0/0x140 net/core/net_namespace.c:178 cleanup_net+0x430/0x890 net/core/net_namespace.c:626 process_one_work+0x7b8/0x189c kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x730/0xb74 kernel/workqueue.c:3391 kthread+0x27c/0x300 kernel/kthread.c:389 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 INFO: task syz.1.486:5041 blocked for more than 430 seconds. Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.486 state:D stack:0 pid:5041 tgid:5041 ppid:3278 flags:0x0040000d Call trace: __switch_to+0x204/0x39c arch/arm64/kernel/process.c:606 context_switch kernel/sched/core.c:5328 [inline] __schedule+0xafc/0x2df4 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xd0/0x304 kernel/sched/core.c:6782 schedule_timeout+0x1fc/0x234 kernel/time/timer.c:2591 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x1d0/0x4ac kernel/sched/completion.c:116 wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x20/0x2c kernel/sched/completion.c:148 rcu_barrier kernel/rcu/tree.c:4630 [inline] rcu_barrier+0x294/0x594 kernel/rcu/tree.c:4551 netdev_run_todo+0x250/0xd04 net/core/dev.c:10782 rtnl_unlock+0x10/0x1c net/core/rtnetlink.c:152 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0x90/0x1ac drivers/net/tun.c:3517 __fput+0x2c4/0x944 fs/file_table.c:431 ____fput+0x14/0x20 fs/file_table.c:459 task_work_run+0x128/0x210 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] do_notify_resume+0x1d4/0x25c arch/arm64/kernel/entry-common.c:151 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline] el0_svc_compat+0xfc/0x17c arch/arm64/kernel/entry-common.c:853 el0t_32_sync_handler+0x98/0x13c arch/arm64/kernel/entry-common.c:862 el0t_32_sync+0x194/0x198 arch/arm64/kernel/entry.S:603 Showing all locks held in the system: 2 locks held by ksoftirqd/0/15: 1 lock held by khungtaskd/31: #0: ffff800086e064e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x48/0x340 kernel/locking/lockdep.c:6714 3 locks held by kworker/u8:2/35: 1 lock held by syslogd/3081: 2 locks held by getty/3216: #0: ffff00001796b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff80008ceab2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x93c/0xe9c drivers/tty/n_tty.c:2211 4 locks held by kworker/u8:0/4234: #0: ffff00000d95a148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x6e4/0x189c kernel/workqueue.c:3204 #1: ffff8000a03b7ce0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x708/0x189c kernel/workqueue.c:3204 #2: ffff800088187430 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xcc/0x890 net/core/net_namespace.c:580 #3: ffff800086e0ee40 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x594 kernel/rcu/tree.c:4562 3 locks held by kworker/u8:5/4567: 1 lock held by syz.1.486/5041: #0: ffff800086e0ee40 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x594 kernel/rcu/tree.c:4562 2 locks held by syz.3.664/5545: 1 lock held by syz.3.664/5548: #0: ffff00000ef61988 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock_killable include/linux/mmap_lock.h:153 [inline] #0: ffff00000ef61988 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:6112 [inline] #0: ffff00000ef61988 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0xdc/0x474 mm/memory.c:6163 2 locks held by syz.2.665/5547: =============================================