INFO: task syz.1.227:6694 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.1.227 state:D stack:26720 pid:6694 tgid:6693 ppid:5851 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ea/0x5050 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 chrdev_open+0x4cd/0x5e0 fs/char_dev.c:414 do_dentry_open+0x7ce/0x1420 fs/open.c:962 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:4637 [inline] path_openat+0x3486/0x3e20 fs/namei.c:4796 do_filp_open+0x22d/0x490 fs/namei.c:4823 do_sys_openat2+0x12f/0x220 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa80075b78e RSP: 002b:00007fa80167cb28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fa80167d6c0 RCX: 00007fa80075b78e RDX: 0000000000000002 RSI: 00007fa80167cc00 RDI: ffffffffffffff9c RBP: 00007fa800808c1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa800a16038 R14: 00007fa800a15fa0 R15: 00007fa800b3fa48 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:5/1000: 4 locks held by kworker/u8:6/1096: 2 locks held by getty/5589: #0: ffff88814e0450a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 6 locks held by kworker/0:5/5897: 4 locks held by syz.2.214/6648: 1 lock held by syz.1.227/6694: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 1 lock held by syz.3.279/6897: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 1 lock held by syz.4.317/7021: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 1 lock held by syz.6.334/7090: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 2 locks held by syz.5.337/7128: #0: ffff8880788d4540 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:182 #1: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: t_start+0x1b/0x50 fs/proc/proc_tty.c:106 1 lock held by syz.7.330/7164: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: ptmx_open+0x108/0x340 drivers/tty/pty.c:798 1 lock held by syz.0.353/7258: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 1 lock held by syz.2.368/7337: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: ptmx_open+0x108/0x340 drivers/tty/pty.c:798 1 lock held by syz.1.426/7576: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 1 lock held by syz.3.457/7674: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 1 lock held by syz.5.517/7885: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 1 lock held by syz.4.535/7954: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 1 lock held by syz.9.584/8133: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 2 locks held by syz-executor/8306: 1 lock held by syz.0.635/8324: 1 lock held by syz.0.635/8325: #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline] #0: ffffffff8edd7888 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120 2 locks held by syz.6.638/8334: 1 lock held by syz-executor/8335: ============================================= NMI backtrace for cpu 0 CPU: 0 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 01/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5833 Comm: kworker/1:3 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: wg-crypt-wg0 wg_packet_encrypt_worker RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:229 [inline] RIP: 0010:unwind_next_frame+0x223/0x23c0 arch/x86/kernel/unwind_orc.c:510 Code: 86 78 04 00 00 44 89 f8 4c 8d 2c 85 4c ef 2d 91 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 48 89 eb 0f 85 25 1c 00 00 45 8b 6d 00 <44> 89 f8 ff c0 48 8d 2c 85 4c ef 2d 91 48 89 e8 48 c1 e8 03 0f b6 RSP: 0018:ffffc9000494ef18 EFLAGS: 00000046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000080000000 RDX: 00000000000a9ac5 RSI: ffffffff8c073a60 RDI: ffffffff8c073a20 RBP: dffffc0000000000 R08: ffffffff81759195 R09: ffffffff8e55a360 R10: ffffc9000494f038 R11: ffffffff81afb170 R12: ffffffff866071c8 R13: 00000000000f7b99 R14: ffffc9000494efe8 R15: 0000000000056071 FS: 0000000000000000(0000) GS:ffff8881257f5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f56537abb40 CR3: 0000000096f4a000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 insert_work+0x3d/0x330 kernel/workqueue.c:2180 __queue_work+0xccf/0xf90 kernel/workqueue.c:2335 queue_work_on+0x106/0x1d0 kernel/workqueue.c:2386 wg_queue_enqueue_per_peer_tx+0x3c9/0x450 drivers/net/wireguard/queueing.h:183 wg_packet_encrypt_worker+0x1395/0x1740 drivers/net/wireguard/send.c:305 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0xda6/0x1360 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246