INFO: task kworker/u8:3:44 blocked for more than 143 seconds. Not tainted 6.16.0-rc5-syzkaller-00025-gd006330be3f7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:3 state:D stack:22360 pid:44 tgid:44 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6790 __schedule_loop kernel/sched/core.c:6868 [inline] schedule+0x165/0x360 kernel/sched/core.c:6883 afs_cell_purge+0x3d9/0x540 fs/afs/cell.c:893 afs_net_exit+0x50/0x100 fs/afs/main.c:147 ops_exit_list net/core/net_namespace.c:200 [inline] ops_undo_list+0x49a/0x990 net/core/net_namespace.c:253 cleanup_net+0x4c5/0x800 net/core/net_namespace.c:686 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 3 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/31: #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 3 locks held by kworker/u8:3/44: #0: ffff88801b2fb948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b2fb948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc90000b47bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000b47bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f4fe910 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:662 3 locks held by kworker/u8:4/59: #0: ffff88814c6b6948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88814c6b6948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffff8880b8623f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 #2: ffff888021bf8768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6062 [inline] #2: ffff888021bf8768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xc4/0x460 net/wireless/core.c:421 2 locks held by getty/5599: #0: ffff888030fbf0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/1:3/5849: #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc9000420fbc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000420fbc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffff88807ba25240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490 2 locks held by kworker/u8:8/7261: 2 locks held by syz-executor/9227: #0: ffff88804d26a0e0 (&type->s_umount_key#88){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88804d26a0e0 (&type->s_umount_key#88){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88804d26a0e0 (&type->s_umount_key#88){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786 2 locks held by syz-executor/10393: #0: ffff8880b8739e18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606 #1: ffff8880b8723f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 1 lock held by syz.0.596/10536: 3 locks held by syz.5.597/10583: 1 lock held by modprobe/10599: #0: ffff8880b8639e18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606 1 lock held by rm/10600: 2 locks held by modprobe/10601: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-syzkaller-00025-gd006330be3f7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 10602 Comm: modprobe Not tainted 6.16.0-rc5-syzkaller-00025-gd006330be3f7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:check_preemption_disabled+0x12/0x120 lib/smp_processor_id.c:13 Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 0e fe 34 07 <48> 89 44 24 08 65 8b 05 16 fe 34 07 65 8b 0d 0b fe 34 07 f7 c1 ff RSP: 0018:ffffc9000413f480 EFLAGS: 00000082 RAX: d5f376a76661ef00 RBX: 0000000000000000 RCX: d5f376a76661ef00 RDX: 0000000000000000 RSI: ffffffff8db71883 RDI: ffffffff8be1ca40 RBP: ffffffff822cb02a R08: 0000000000000000 R09: ffffffff822cb02a R10: dffffc0000000000 R11: fffff940009ffcf1 R12: 0000000000000002 R13: ffffffff8e13f220 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff888125c4f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8444665e9c CR3: 000000000df38000 CR4: 00000000003526f0 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:473 [inline] lock_acquire+0x130/0x360 kernel/locking/lockdep.c:5873 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock_sched include/linux/rcupdate.h:932 [inline] pfn_valid+0xd6/0x490 include/linux/mmzone.h:2158 page_table_check_clear+0x21/0x700 mm/page_table_check.c:70 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline] get_and_clear_full_ptes include/linux/pgtable.h:714 [inline] zap_present_folio_ptes mm/memory.c:1505 [inline] zap_present_ptes mm/memory.c:1590 [inline] do_zap_pte_range mm/memory.c:1691 [inline] zap_pte_range mm/memory.c:1735 [inline] zap_pmd_range mm/memory.c:1827 [inline] zap_pud_range mm/memory.c:1856 [inline] zap_p4d_range mm/memory.c:1877 [inline] unmap_page_range+0x3249/0x41c0 mm/memory.c:1898 unmap_single_vma mm/memory.c:1941 [inline] unmap_vmas+0x399/0x580 mm/memory.c:1985 exit_mmap+0x248/0xb50 mm/mmap.c:1284 __mmput+0x118/0x410 kernel/fork.c:1121 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x648/0x22e0 kernel/exit.c:952 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105 __do_sys_exit_group kernel/exit.c:1116 [inline] __se_sys_exit_group kernel/exit.c:1114 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1114 x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f84447c46c5 Code: Unable to access opcode bytes at 0x7f84447c469b. RSP: 002b:00007fffd82cff98 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f84448c5fe8 RCX: 00007f84447c46c5 RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000001 RBP: 0000000000000001 R08: 00007fffd82cff28 R09: 0000000000000000 R10: 00007fffd82cfdc0 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f84448c4680 R15: 00007f84448c6000