INFO: task kworker/u4:1:9936 blocked for more than 170 seconds. Not tainted 6.8.0-rc2-next-20240202-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:1 state:D stack:22608 pid:9936 tgid:9936 ppid:2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x17df/0x4a40 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6804 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6819 schedule_timeout+0xb0/0x310 kernel/time/timer.c:2159 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x355/0x620 kernel/sched/completion.c:148 __flush_workqueue+0x730/0x1630 kernel/workqueue.c:3617 drain_workqueue+0xc9/0x390 kernel/workqueue.c:3730 destroy_workqueue+0xba/0xc40 kernel/workqueue.c:5319 bond_destructor+0x4d/0x80 drivers/net/bonding/bond_main.c:5846 netdev_run_todo+0xd4f/0xf40 net/core/dev.c:10581 default_device_exit_batch+0x975/0x9f0 net/core/dev.c:11625 ops_exit_list net/core/net_namespace.c:175 [inline] cleanup_net+0x775/0xb90 net/core/net_namespace.c:618 process_one_work kernel/workqueue.c:3049 [inline] process_scheduled_works+0x913/0x14f0 kernel/workqueue.c:3125 worker_thread+0xa60/0x1000 kernel/workqueue.c:3206 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 3 locks held by kworker/1:2/1727: #0: ffff888014c7cd48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3024 [inline] #0: ffff888014c7cd48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x14f0 kernel/workqueue.c:3125 #1: ffffc900054afd20 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3024 [inline] #1: ffffc900054afd20 (fqdir_free_work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x14f0 kernel/workqueue.c:3125 #2: ffffffff8e135fc0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x550 kernel/rcu/tree.c:4073 2 locks held by getty/4829: #0: ffff88802aa5b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201 3 locks held by kworker/u4:1/9936: #0: ffff888015acd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3024 [inline] #0: ffff888015acd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x14f0 kernel/workqueue.c:3125 #1: ffffc90004fbfd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3024 [inline] #1: ffffc90004fbfd20 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x14f0 kernel/workqueue.c:3125 #2: ffffffff8f36da50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf5/0xb90 net/core/net_namespace.c:580 2 locks held by syz-executor.2/12702: #0: ffffffff8f36da50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c8/0x7b0 net/core/net_namespace.c:491 #1: ffffffff8e135fc0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x550 kernel/rcu/tree.c:4073 4 locks held by syz-executor.3/12861: #0: ffffffff8e8fa1e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 #1: ffffffff8dfe51c8 (system_transition_mutex){+.+.}-{3:3}, at: lock_system_sleep+0x60/0xa0 kernel/power/main.c:56 #2: ffffffff8e004f10 ((pm_chain_head).rwsem){++++}-{3:3}, at: blocking_notifier_call_chain_robust+0xac/0x1e0 kernel/notifier.c:352 #3: ffffffff8e135fc0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x550 kernel/rcu/tree.c:4073 1 lock held by syz-executor.3/12863: #0: ffffffff8e8fa1e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x390 drivers/char/misc.c:129 2 locks held by syz-executor.3/12866: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc2-next-20240202-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfb0/0xff0 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 12866 Comm: syz-executor.3 Not tainted 6.8.0-rc2-next-20240202-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline] RIP: 0010:do_raw_spin_lock+0x83/0x370 kernel/locking/spinlock_debug.c:115 Code: 40 48 c1 ee 03 48 b8 f1 f1 f1 f1 04 f3 f3 f3 48 89 f1 48 89 74 24 38 48 89 04 16 48 8d 5f 04 48 89 d8 48 c1 e8 03 0f b6 04 10 <84> c0 0f 85 f6 01 00 00 8b 03 3d ad 4e ad de 0f 85 62 01 00 00 4d RSP: 0018:ffffc90004a0f3c0 EFLAGS: 00000807 RAX: 0000000000000000 RBX: ffff8880172ba7fc RCX: 1ffff92000941e80 RDX: dffffc0000000000 RSI: 1ffff92000941e80 RDI: ffff8880172ba7f8 RBP: ffffc90004a0f490 R08: ffffffff92ca3437 R09: 1ffffffff2594686 R10: dffffc0000000000 R11: fffffbfff2594687 R12: ffff8880172ba7f8 R13: 1ffff92000941e94 R14: ffff8880172ba7f8 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa2ee17c038 CR3: 0000000076704000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0xe1/0x120 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:553 [inline] try_to_wake_up+0xb0/0x1470 kernel/sched/core.c:4253 kthread_queue_work+0xff/0x180 kernel/kthread.c:1021 synchronize_rcu_expedited_queue_work kernel/rcu/tree_exp.h:469 [inline] synchronize_rcu_expedited+0x593/0x820 kernel/rcu/tree_exp.h:949 namespace_unlock+0x29f/0x4d0 fs/namespace.c:1573 drop_collected_mounts fs/namespace.c:2078 [inline] put_mnt_ns+0xdc/0x120 fs/namespace.c:5196 free_nsproxy+0x4d/0x3b0 kernel/nsproxy.c:193 do_exit+0xa16/0x27e0 kernel/exit.c:877 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 get_signal+0x176e/0x1850 kernel/signal.c:2896 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:225 exc_page_fault+0x585/0x890 arch/x86/mm/fault.c:1575 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fa2ee028807 Code: Unable to access opcode bytes at 0x7fa2ee0287dd. RSP: 002b:0000000020000560 EFLAGS: 00010206 RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007fa2ee07dda9 RDX: 0000000020000580 RSI: 00000000200006b0 RDI: 000000000000000b RBP: 00007fa2ee0ca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020002340 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000006e R14: 00007fa2ee1ac050 R15: 00007ffce223e078