INFO: task kworker/u8:16:6150 blocked for more than 144 seconds. Not tainted 6.14.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:16 state:D stack:26512 pid:6150 tgid:6150 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events_unbound flush_to_ldisc Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 commit_echoes+0x4c/0x210 drivers/tty/n_tty.c:756 n_tty_receive_char+0x3d8/0x600 drivers/tty/n_tty.c:1437 n_tty_receive_buf_standard+0x6aa/0x3180 drivers/tty/n_tty.c:1606 __receive_buf drivers/tty/n_tty.c:1640 [inline] n_tty_receive_buf_common+0x347/0x18e0 drivers/tty/n_tty.c:1739 tty_ldisc_receive_buf+0xa2/0x190 drivers/tty/tty_buffer.c:387 tty_port_default_receive_buf+0x70/0xb0 drivers/tty/tty_port.c:37 receive_buf drivers/tty/tty_buffer.c:445 [inline] flush_to_ldisc+0x264/0x780 drivers/tty/tty_buffer.c:495 process_one_work+0x958/0x1b30 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by kthreadd/2: 2 locks held by kworker/0:0/8: 2 locks held by kworker/u8:1/12: 1 lock held by kworker/R-mm_pe/13: 1 lock held by khungtaskd/30: #0: ffffffff8e1bc140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bc140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bc140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 2 locks held by kworker/1:1/57: 2 locks held by syslogd/5189: 1 lock held by klogd/5196: 1 lock held by dhcpcd/5500: 4 locks held by dhcpcd/5501: 2 locks held by getty/5591: #0: ffff8880319b30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 2 locks held by kworker/0:1/5845: 2 locks held by syz-executor/5848: 1 lock held by syz-executor/5857: #0: ffffffff8fed7e68 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:702 [inline] #0: ffffffff8fed7e68 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3521 2 locks held by syz-executor/5858: 2 locks held by syz-executor/5860: 4 locks held by kworker/0:3/5864: #0: ffff88801b081d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3211 #1: ffffc9000436fd18 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3212 #2: ffffffff8fed7e68 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x84/0x1130 net/wireless/reg.c:2480 #3: ffff8880680d0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6061 [inline] #3: ffff8880680d0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2468 [inline] #3: ffff8880680d0768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x111/0x1130 net/wireless/reg.c:2483 1 lock held by kworker/R-wg-cr/5884: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 1 lock held by kworker/R-wg-cr/5889: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 1 lock held by kworker/R-wg-cr/5890: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 1 lock held by kworker/R-wg-cr/5891: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 1 lock held by kworker/R-wg-cr/5892: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 1 lock held by kworker/R-wg-cr/5893: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 1 lock held by kworker/R-wg-cr/5894: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 1 lock held by kworker/R-wg-cr/5896: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 1 lock held by kworker/R-wg-cr/5897: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2676 5 locks held by kworker/u8:2/5899: 4 locks held by kworker/1:3/5900: 3 locks held by kworker/0:4/5901: 2 locks held by kworker/0:5/5902: 3 locks held by kworker/u8:3/5905: 3 locks held by kworker/u8:4/5914: 2 locks held by kworker/0:6/5921: 1 lock held by kworker/1:4/5923: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2676 2 locks held by kworker/1:5/5960: 3 locks held by kworker/u8:7/6141: 3 locks held by kworker/u8:11/6145: 3 locks held by kworker/u8:15/6149: 6 locks held by kworker/u8:16/6150: #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3211 #1: ffffc90005127d18 ((work_completion)(&buf->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3212 #2: ffff88805f46e0b8 (&buf->lock){+.+.}-{4:4}, at: flush_to_ldisc+0x31/0x780 drivers/tty/tty_buffer.c:467 #3: ffff888033a780a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1c/0x80 drivers/tty/tty_ldisc.c:263 #4: ffff888033a782e8 (&tty->termios_rwsem){++++}-{4:4}, at: n_tty_receive_buf_common+0x85/0x18e0 drivers/tty/n_tty.c:1702 #5: ffffc900050fb380 (&ldata->output_lock){+.+.}-{4:4}, at: commit_echoes+0x4c/0x210 drivers/tty/n_tty.c:756 3 locks held by kworker/u8:17/6151: 3 locks held by kworker/u8:18/6152: 3 locks held by kworker/u8:20/6154: #0: ffff888030cfd948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3211 #1: ffffc90005177d18 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3212 #2: ffffffff8fed7e68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #2: ffffffff8fed7e68 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4730 4 locks held by kworker/u8:22/6450: #0: ffff88801bef5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3211 #1: ffffc9000c3f7d18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3212 #2: ffffffff8fec1e90 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xca/0xbf0 net/core/net_namespace.c:606 #3: ffffffff8fed7e68 (rtnl_mutex){+.+.}-{4:4}, at: mpls_net_exit+0x83/0x350 net/mpls/af_mpls.c:2706 3 locks held by kworker/u8:23/6451: 4 locks held by kworker/u8:24/6453: #0: ffff8881437f4148 ((wq_completion)wg-kex-wg0){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3211 #1: ffffc9000dc47d18 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3212 #2: ffff888024889308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0xed/0x650 drivers/net/wireguard/noise.c:529 #3: ffff8880609f8338 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x101/0x650 drivers/net/wireguard/noise.c:530 2 locks held by syz-executor/6808: 1 lock held by kworker/R-wg-cr/6822: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 1 lock held by kworker/R-wg-cr/6825: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 1 lock held by kworker/R-wg-cr/6826: #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2734 [inline] #0: ffffffff8e075788 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x856/0xe20 kernel/workqueue.c:3533 6 locks held by syz.2.322/7400: 4 locks held by kworker/1:6/7409: #0: ffff888033a6c148 ((wq_completion)wg-kex-wg2#2){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3211 #1: ffffc900041ffd18 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((typeof(*((worker))) *)(( unsigned long)((worker))))); (typeof((typeof(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3212 #2: ffff8880623c5308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c3/0xaa0 drivers/net/wireguard/noise.c:598 #3: ffff8880609fa938 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5a3/0xaa0 drivers/net/wireguard/noise.c:632 3 locks held by kworker/0:7/7410: 2 locks held by syz-executor/7411: 2 locks held by kworker/1:7/7412: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5899 Comm: kworker/u8:2 Not tainted 6.14.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:__orc_find+0x3d/0xf0 arch/x86/kernel/unwind_orc.c:104 Code: 53 48 83 ec 08 85 d2 0f 84 99 00 00 00 49 39 fc 49 89 fe 48 89 f0 72 7b 48 b9 00 00 00 00 00 fc ff df 49 89 ff 48 89 fd eb 0c <48> 8d 6b 04 49 89 df 49 39 ec 72 4e 4c 89 e2 48 29 ea 48 89 d6 48 RSP: 0018:ffffc90000a17ea8 EFLAGS: 00000202 RAX: ffffffff918d4e24 RBX: ffffffff90d8519c RCX: dffffc0000000000 RDX: ffffffff8a1afb20 RSI: 0000000000000000 RDI: ffffffff90d8519c RBP: ffffffff90d8519c R08: ffffffff918d4e2a R09: ffffffff918d4c8a R10: ffffc90000a17f58 R11: 0000000000091afc R12: ffffffff90d8519c R13: ffffffff8a1afc40 R14: ffffffff90d8519c R15: ffffffff90d8519c FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff4a8f78ab8 CR3: 000000000df80000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: orc_find arch/x86/kernel/unwind_orc.c:227 [inline] unwind_next_frame+0x2be/0x20c0 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x95/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] kmem_cache_alloc_noprof+0x1c8/0x3b0 mm/slub.c:4171 skb_clone+0x190/0x3f0 net/core/skbuff.c:2084 deliver_clone+0x3f/0xa0 net/bridge/br_forward.c:125 br_flood+0x491/0x5e0 net/bridge/br_forward.c:249 br_handle_frame_finish+0xea2/0x1c90 net/bridge/br_input.c:220 br_nf_hook_thresh+0x303/0x410 net/bridge/br_netfilter_hooks.c:1170 br_nf_pre_routing_finish_ipv6+0x76a/0xfb0 net/bridge/br_netfilter_ipv6.c:154 NF_HOOK include/linux/netfilter.h:314 [inline] br_nf_pre_routing_ipv6+0x3ce/0x8c0 net/bridge/br_netfilter_ipv6.c:184 br_nf_pre_routing+0x860/0x15b0 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:282 [inline] br_handle_frame+0xa81/0x14c0 net/bridge/br_input.c:433 __netif_receive_skb_core.constprop.0+0xa20/0x4330 net/core/dev.c:5722 __netif_receive_skb_one_core+0xb1/0x1e0 net/core/dev.c:5826 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5941 process_backlog+0x443/0x15f0 net/core/dev.c:6289 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7106 napi_poll net/core/dev.c:7175 [inline] net_rx_action+0xa94/0x1010 net/core/dev.c:7297 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 do_softirq kernel/softirq.c:462 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:449 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:389 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x8de/0xd20 drivers/net/netdevsim/dev.c:851 process_one_work+0x958/0x1b30 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244