INFO: task syz.3.32:4374 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.32 state:D stack:24624 pid: 4374 ppid: 4185 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127 _free_event+0x34/0xe60 kernel/events/core.c:5133 put_event kernel/events/core.c:5258 [inline] perf_event_release_kernel+0x83e/0x8d0 kernel/events/core.c:5383 perf_release+0x37/0x40 kernel/events/core.c:5393 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x626/0x20c0 kernel/exit.c:883 do_group_exit+0x12e/0x300 kernel/exit.c:997 get_signal+0x6ca/0x12c0 kernel/signal.c:2900 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f4ee8c5c819 RSP: 002b:00007f4ee6eb6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: 0000000000033fe0 RBX: 00007f4ee8ed5fa0 RCX: 00007f4ee8c5c819 RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000008 RBP: 00007f4ee8cf2c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4ee8ed6038 R14: 00007f4ee8ed5fa0 R15: 00007ffe33eb3ec8 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c31eb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 5 locks held by kworker/u4:4/1235: #0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc900056f7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 #2: ffffffff8d431510 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589 #3: ffff88805f0e13e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_destruct+0x112/0x300 drivers/net/wireguard/device.c:233 #4: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #4: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845 2 locks held by dhcpcd/3853: #0: ffffffff8d425888 (vlan_ioctl_mutex){+.+.}-{3:3}, at: sock_ioctl+0x25a/0x710 net/socket.c:1228 #1: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: vlan_ioctl_handler+0xef/0x5d0 net/8021q/vlan.c:581 2 locks held by getty/3946: #0: ffff88814cdf2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158 2 locks held by kworker/1:6/4234: #0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc9000313fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 2 locks held by kworker/0:12/5020: 4 locks held by kworker/u4:8/6187: #0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc90003357d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 #2: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 #3: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #3: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845 2 locks held by syz.4.843/7701: #0: ffffffff8d431510 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499 #1: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit+0xe/0x20 net/can/gw.c:1279 3 locks held by syz.6.858/7775: 2 locks held by syz.2.864/7819: #0: ffffffff8d431510 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499 #1: ffffffff8c3234b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4c0 kernel/rcu/tree.c:4043 2 locks held by syz.0.870/7835: #0: ffffffff8cccf7a8 (ppp_mutex){+.+.}-{3:3}, at: ppp_ioctl+0xdc/0x1a80 drivers/net/ppp/ppp_generic.c:738 #1: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: ppp_create_interface drivers/net/ppp/ppp_generic.c:3359 [inline] #1: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1069 [inline] #1: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: ppp_ioctl+0x689/0x1a80 drivers/net/ppp/ppp_generic.c:742 1 lock held by syz.0.870/7836: #0: ffffffff8cccf7a8 (ppp_mutex){+.+.}-{3:3}, at: ppp_ioctl+0xdc/0x1a80 drivers/net/ppp/ppp_generic.c:738 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7701 Comm: syz.4.843 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:__kasan_check_read+0x6/0x10 mm/kasan/shadow.c:31 Code: 41 5f 5d c3 48 c7 c7 2a f0 de 8b eb 0a 48 c7 c7 b6 1b c5 8b 48 89 de e8 e8 dc f3 07 31 ed eb d7 00 00 cc cc 89 f6 48 8b 0c 24 <31> d2 e9 43 ef ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01 00 00 00 e9 RSP: 0018:ffffc9000311f398 EFLAGS: 00000002 RAX: 0000000000000008 RBX: 0000000000000000 RCX: ffffffff815d1f15 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff901d50c8 RBP: ffffc9000311f5f0 R08: dffffc0000000000 R09: 1ffffffff203aa18 R10: dffffc0000000000 R11: fffffbfff203aa19 R12: ffff888076f728d0 R13: ffff888076f72804 R14: 000000000000006c R15: ffff888076f728d0 FS: 00007f5b7bd7e6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f09b58c52f8 CR3: 000000007b1f0000 CR4: 00000000003506e0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] hlock_class kernel/locking/lockdep.c:197 [inline] check_wait_context kernel/locking/lockdep.c:4711 [inline] __lock_acquire+0x925/0x7d10 kernel/locking/lockdep.c:4962 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313 rcu_read_lock include/linux/rcupdate.h:740 [inline] inet_twsk_purge+0x119/0x840 net/ipv4/inet_timewait_sock.c:268 ops_exit_list net/core/net_namespace.c:177 [inline] setup_net+0x844/0xa10 net/core/net_namespace.c:365 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 copy_namespaces+0x37d/0x3e0 kernel/nsproxy.c:178 copy_process+0x1834/0x3e20 kernel/fork.c:2293 kernel_clone+0x23f/0x990 kernel/fork.c:2679 __do_sys_clone kernel/fork.c:2796 [inline] __se_sys_clone kernel/fork.c:2780 [inline] __x64_sys_clone+0x19a/0x210 kernel/fork.c:2780 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f5b7db24819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5b7bd7dfd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f5b7dd9dfa0 RCX: 00007f5b7db24819 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000042164000 RBP: 00007f5b7dbbac91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f5b7dd9e038 R14: 00007f5b7dd9dfa0 R15: 00007ffe34bef8d8