INFO: task kworker/u8:10:2982 blocked for more than 143 seconds. Not tainted 6.11.0-rc5-syzkaller-00057-g86987d84b968 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:10 state:D stack:23536 pid:2982 tgid:2982 ppid:2 flags:0x00004000 Workqueue: events_unbound linkwatch_event Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 linkwatch_event+0x51/0xc0 net/core/link_watch.c:276 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8ddb5d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8ddb5d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8ddb5d20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6626 4 locks held by kworker/1:1/46: 4 locks held by kworker/u8:5/941: 2 locks held by kworker/u8:7/1296: 3 locks held by kworker/u8:10/2982: #0: ffff888015889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc90009edfd80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffffffff8fa238e8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:276 5 locks held by kworker/u8:11/3013: 3 locks held by syslogd/4653: 3 locks held by udevd/4671: 2 locks held by getty/4973: #0: ffff88802b8cd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000311b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:3/5219: 1 lock held by syz-executor/5220: 1 lock held by syz-executor/5221: #0: ffffffff8fa238e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fa238e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x230 drivers/net/tun.c:3510 1 lock held by syz-executor/5222: #0: ffffffff8fa238e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fa238e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x230 drivers/net/tun.c:3510 2 locks held by syz-executor/5223: #0: ffffffff8fa238e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fa238e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x230 drivers/net/tun.c:3510 #1: ffffffff8ddc14b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:328 1 lock held by syz-executor/5232: #0: ffffffff8fa238e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fa238e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x230 drivers/net/tun.c:3510 2 locks held by kworker/0:3/5272: 2 locks held by kworker/1:5/5307: 4 locks held by kworker/0:7/7156: 2 locks held by kworker/u8:12/7577: 3 locks held by kworker/u8:16/7591: #0: ffff88802b1fb948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc900042ffd80 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffffffff8fa238e8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4734 3 locks held by kworker/0:9/11875: 1 lock held by udevd/11879: 2 locks held by kworker/0:12/11883: 4 locks held by syz-executor/11884: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc5-syzkaller-00057-g86987d84b968 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 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:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 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: 3013 Comm: kworker/u8:11 Not tainted 6.11.0-rc5-syzkaller-00057-g86987d84b968 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: bat_events batadv_dat_purge RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:218 [inline] RIP: 0010:unwind_next_frame+0x2b4/0x23a0 arch/x86/kernel/unwind_orc.c:494 Code: 83 c5 01 4a 8d 3c ad bc 60 5b 91 48 89 fa 48 c1 ea 03 89 44 24 28 48 b8 00 00 00 00 00 fc ff df 0f b6 14 02 48 89 f8 83 e0 07 <83> c0 03 38 d0 7c 09 84 d2 74 05 e8 6c c1 aa 00 44 8b 74 24 28 42 RSP: 0018:ffffc90000a17eb8 EFLAGS: 00000202 RAX: 0000000000000004 RBX: ffffc90000a17f38 RCX: ffffffff813ce13d RDX: 0000000000000000 RSI: ffffffff813ce14b RDI: ffffffff917b129c RBP: 0000000000000002 R08: 0000000000000004 R09: 000000000007ec77 R10: 00000000000a4000 R11: 0000000000000000 R12: ffffffff88ec776c R13: 000000000007ec78 R14: 000000000007ec77 R15: ffffc90000a17f6d FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd80cc21441 CR3: 000000000db7c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x100/0x170 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:312 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4044 skb_clone+0x190/0x3f0 net/core/skbuff.c:2071 deliver_clone+0x3f/0xa0 net/bridge/br_forward.c:125 maybe_deliver+0xa7/0x120 net/bridge/br_forward.c:190 br_flood+0x17e/0x5c0 net/bridge/br_forward.c:236 br_handle_frame_finish+0xda5/0x1c80 net/bridge/br_input.c:215 br_nf_hook_thresh+0x303/0x410 net/bridge/br_netfilter_hooks.c:1189 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:531 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x9eb/0x1490 net/bridge/br_input.c:424 __netif_receive_skb_core.constprop.0+0xa3d/0x4330 net/core/dev.c:5555 __netif_receive_skb_one_core+0xb1/0x1e0 net/core/dev.c:5659 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5775 process_backlog+0x443/0x15f0 net/core/dev.c:6108 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6772 napi_poll net/core/dev.c:6841 [inline] net_rx_action+0xa92/0x1010 net/core/dev.c:6963 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554 do_softirq kernel/softirq.c:455 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:442 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382 spin_unlock_bh include/linux/spinlock.h:396 [inline] __batadv_dat_purge.part.0+0x279/0x3a0 net/batman-adv/distributed-arp-table.c:186 __batadv_dat_purge net/batman-adv/distributed-arp-table.c:167 [inline] batadv_dat_purge+0x4b/0xa0 net/batman-adv/distributed-arp-table.c:205 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244