INFO: task syz.2.3346:19326 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.3346 state:D stack:26552 pid:19326 tgid:19325 ppid:15503 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 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_work+0x7c7/0xcb0 kernel/workqueue.c:4366 p9_mux_poll_stop net/9p/trans_fd.c:140 [inline] p9_conn_destroy net/9p/trans_fd.c:804 [inline] p9_fd_close+0x299/0x5a0 net/9p/trans_fd.c:840 p9_client_create+0x678/0xd40 net/9p/client.c:937 v9fs_session_init+0x3c/0xd20 fs/9p/v9fs.c:446 v9fs_get_tree+0xb8/0xb50 fs/9p/vfs_super.c:97 vfs_get_tree+0x92/0x320 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3761 [inline] do_new_mount fs/namespace.c:3837 [inline] path_mount+0x7d0/0x23d0 fs/namespace.c:4157 do_mount fs/namespace.c:4170 [inline] __do_sys_mount fs/namespace.c:4386 [inline] __se_sys_mount fs/namespace.c:4363 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:4363 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1b6d19ce59 RSP: 002b:00007f1b6df80028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f1b6d415fa0 RCX: 00007f1b6d19ce59 RDX: 00002000000000c0 RSI: 0000200000000c40 RDI: 0000000000000000 RBP: 00007f1b6d232d6f R08: 0000200000000c80 R09: 0000000000000000 R10: 0000000000200000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1b6d416038 R14: 00007f1b6d415fa0 R15: 00007ffe0203a5b8 Showing all locks held in the system: 2 locks held by kworker/0:0/9: #0: ffff88813fe57140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc900000e7d08 (p9_poll_work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 1 lock held by khungtaskd/31: #0: ffffffff8e7e5560 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e7e5560 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e7e5560 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by getty/5372: #0: ffff888037a2f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211 2 locks held by kworker/1:4/5711: 1 lock held by syz.8.3829/21271: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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:162 [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:353 [inline] watchdog+0xcb1/0x1030 kernel/hung_task.c:561 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 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: 156 Comm: kworker/u8:6 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker RIP: 0010:__bfs+0x1c7/0x2a0 kernel/locking/lockdep.c:1815 Code: 81 e3 ff 0f 00 00 39 1d 27 25 2c 14 48 89 04 f5 00 5c cb 96 73 11 89 1d 17 25 2c 14 eb 09 0f 1f 44 00 00 4c 89 78 30 48 8b 00 <4c> 39 c0 75 f4 e9 22 ff ff ff b8 01 00 00 00 48 83 c4 30 5b 5d 41 RSP: 0018:ffffc90002f56c08 EFLAGS: 00000006 RAX: ffffffff97a50058 RBX: 0000000000000112 RCX: 0000000000000113 RDX: ffffffff9616a0d8 RSI: 0000000000000113 RDI: ffffffff97a4aa98 RBP: 0000000000000030 R08: ffffffff9616a108 R09: 0000000000000002 R10: ffffc90002f56d98 R11: 0000000000000000 R12: ffffffff81e41960 R13: ffffc90002f56cb0 R14: ffffffff81e42770 R15: ffffffff97a4aa98 FS: 0000000000000000(0000) GS:ffff888124387000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc8bb1ec4b8 CR3: 0000000035e3e000 CR4: 00000000003526f0 Call Trace: __bfs_backwards kernel/locking/lockdep.c:1860 [inline] check_irq_usage+0xe5/0x810 kernel/locking/lockdep.c:2796 check_prev_add kernel/locking/lockdep.c:3169 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x14cf/0x2630 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b1/0x370 kernel/locking/lockdep.c:5825 seqcount_lockdep_reader_access include/linux/seqlock.h:73 [inline] ktime_get+0x7c/0x320 kernel/time/timekeeping.c:965 clockevents_program_event+0x23e/0x820 kernel/time/clockevents.c:363 tick_program_event+0xa9/0x140 kernel/time/tick-oneshot.c:48 hrtimer_rearm_event kernel/time/hrtimer.c:707 [inline] hrtimer_rearm kernel/time/hrtimer.c:2039 [inline] __hrtimer_rearm_deferred+0x237/0x740 kernel/time/hrtimer.c:2059 hrtimer_rearm_deferred_tif include/linux/hrtimer_rearm.h:53 [inline] hrtimer_rearm_deferred include/linux/hrtimer_rearm.h:62 [inline] irqentry_exit_to_kernel_mode_after_preempt include/linux/irq-entry-common.h:505 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:542 [inline] irqentry_exit+0x571/0x970 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline] RIP: 0010:vprintk_emit+0x553/0x6b0 kernel/printk/printk.c:2478 Code: 00 4d 85 ed 0f 85 1b 01 00 00 e8 68 62 21 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 36 5d 21 00 48 85 ed 0f 85 27 01 00 00 48 62 21 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00 RSP: 0018:ffffc90002f57158 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000042 RCX: ffffffff81e7504a RDX: ffff888020fd0000 RSI: ffffffff81e75054 RDI: ffff888020fd0000 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff920005eae2d R13: 0000000000000200 R14: ffff88801ee82540 R15: ffffc90002f57220 _printk+0xcf/0x110 kernel/printk/printk.c:2504 gred_dequeue.cold+0x40/0x4f net/sched/sch_gred.c:273 dequeue_skb net/sched/sch_generic.c:322 [inline] qdisc_restart net/sched/sch_generic.c:427 [inline] __qdisc_run+0x1be/0x1af0 net/sched/sch_generic.c:445 qdisc_run include/net/pkt_sched.h:120 [inline] qdisc_run include/net/pkt_sched.h:117 [inline] __dev_xmit_skb net/core/dev.c:4292 [inline] __dev_queue_xmit+0x30ed/0x4950 net/core/dev.c:4831 dev_queue_xmit include/linux/netdevice.h:3418 [inline] neigh_hh_output include/net/neighbour.h:544 [inline] neigh_output include/net/neighbour.h:558 [inline] ip_finish_output2+0xf4a/0x2400 net/ipv4/ip_output.c:237 __ip_finish_output.part.0+0x444/0x6f0 net/ipv4/ip_output.c:315 __ip_finish_output net/ipv4/ip_output.c:303 [inline] ip_finish_output net/ipv4/ip_output.c:325 [inline] NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip_output+0x39b/0xc10 net/ipv4/ip_output.c:438 dst_output include/net/dst.h:470 [inline] ip_local_out+0x193/0x1f0 net/ipv4/ip_output.c:131 iptunnel_xmit+0x722/0xd20 net/ipv4/ip_tunnel_core.c:97 send4+0x414/0x1130 drivers/net/wireguard/socket.c:85 wg_socket_send_skb_to_peer+0x18f/0x210 drivers/net/wireguard/socket.c:174 wg_socket_send_buffer_to_peer+0x148/0x1a0 drivers/net/wireguard/socket.c:199 wg_packet_send_handshake_initiation+0x227/0x360 drivers/net/wireguard/send.c:40 wg_packet_handshake_send_worker+0x1c/0x30 drivers/net/wireguard/send.c:51 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314 process_scheduled_works kernel/workqueue.c:3397 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245