INFO: task kworker/u10:2:12692 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u10:2 state:D stack:26904 pid:12692 tgid:12692 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1023/0x6000 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7004 schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common+0x2e7/0x4c0 kernel/sched/completion.c:121 __flush_workqueue+0x3f7/0x1200 kernel/workqueue.c:4083 rds_tcp_listen_stop+0x104/0x160 net/rds/tcp_listen.c:465 rds_tcp_kill_sock net/rds/tcp.c:605 [inline] rds_tcp_exit_net+0xe0/0x870 net/rds/tcp.c:630 ops_exit_list net/core/net_namespace.c:199 [inline] ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:252 cleanup_net+0x499/0x920 net/core/net_namespace.c:704 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e5e7060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e5e7060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e5e7060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by kworker/0:5/5909: #0: ffff88813fe17548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3250 #1: ffffc90004987d08 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3251 2 locks held by syz.0.175/6795: 4 locks held by kworker/0:1/11582: 3 locks held by kworker/u10:2/12692: #0: ffff88801c2de948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3250 #1: ffffc90003f1fd08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3251 #2: ffffffff903e9470 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:675 1 lock held by syz.5.1376/12982: #0: ffffffff903e9470 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577 1 lock held by syz.6.1464/13344: #0: ffffffff903e9470 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577 1 lock held by syz.1.1501/13521: #0: ffffffff903e9470 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577 2 locks held by getty/13654: #0: ffff8880333990a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900176462f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 1 lock held by /13877: #0: ffffffff903e9470 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577 1 lock held by syz.3.1646/14215: #0: ffffffff903e9470 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577 1 lock held by syz.8.1710/14583: 1 lock held by syz.0.1744/14715: #0: ffffffff8e5f2c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xcc3/0xfe0 kernel/hung_task.c:515 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 13120 Comm: kworker/1:1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: rcu_gp process_srcu RIP: 0010:mark_held_locks+0x25/0x70 kernel/locking/lockdep.c:4317 Code: 90 90 90 90 90 8b 87 00 0b 00 00 85 c0 7e 5a 41 55 49 89 fd 41 54 41 89 f4 55 31 ed 53 48 8d 9f 08 0b 00 00 0f b6 43 22 89 c2 <83> e2 03 80 fa 01 44 89 e2 83 da ff a8 04 74 0f 48 89 de 4c 89 ef RSP: 0018:ffffc90002ec7bd8 EFLAGS: 00000046 RAX: 0000000000000004 RBX: ffff88802ab54788 RCX: 0000000000000000 RDX: 0000000000000004 RSI: 0000000000000002 RDI: ffff88802ab53c80 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 00000000000075b9 R12: 0000000000000002 R13: ffff88802ab53c80 R14: 0000000000000000 R15: ffff88813fec4800 FS: 0000000000000000(0000) GS:ffff8881246a5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005569a97f5ee8 CR3: 0000000037af4000 CR4: 00000000003526f0 Call Trace: __trace_hardirqs_on_caller kernel/locking/lockdep.c:4343 [inline] lockdep_hardirqs_on_prepare kernel/locking/lockdep.c:4410 [inline] lockdep_hardirqs_on_prepare+0xb4/0x1b0 kernel/locking/lockdep.c:4362 trace_hardirqs_on+0x36/0x40 kernel/trace/trace_preemptirq.c:78 queue_delayed_work_on+0x122/0x1e0 kernel/workqueue.c:2578 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245