INFO: task kworker/u8:19:9530 blocked for more than 150 seconds. Not tainted 6.13.0-syzkaller-09710-ga1300691aed9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:19 state:D stack:21104 pid:9530 tgid:9530 ppid:2 task_flags:0x4208160 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 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+0x817/0x1010 kernel/locking/mutex.c:730 rtnl_net_lock include/linux/rtnetlink.h:129 [inline] addrconf_dad_work+0x10e/0x16a0 net/ipv6/addrconf.c:4190 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task kworker/u8:22:9534 blocked for more than 152 seconds. Not tainted 6.13.0-syzkaller-09710-ga1300691aed9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:22 state:D stack:20920 pid:9534 tgid:9534 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events_unbound linkwatch_event Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 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+0x817/0x1010 kernel/locking/mutex.c:730 linkwatch_event+0xe/0x60 net/core/link_watch.c:285 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/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 khungtaskd/30: #0: ffffffff8e938760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e938760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e938760 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 2 locks held by syslogd/5189: 4 locks held by udevd/5207: 2 locks held by getty/5589: #0: ffff888030ffe0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 5 locks held by sshd/5817: 4 locks held by kworker/u8:27/9542: #0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317 #1: ffffc90003547c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90003547c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317 #2: ffffffff8fcb2b10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17a/0xd60 net/core/net_namespace.c:606 #3: ffffffff8e93dc38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline] #3: ffffffff8e93dc38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:996 1 lock held by syz-executor/12256: #0: ffffffff8fcb2b10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512 2 locks held by syz-executor/12257: #0: ffffffff8fcb2b10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512 #1: ffffffff8e93dc38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline] #1: ffffffff8e93dc38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:996 2 locks held by syz-executor/12260: #0: ffffffff8fcb2b10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512 #1: ffffffff8fcbf088 (rtnl_mutex){+.+.}-{4:4}, at: setup_net+0x602/0x9e0 net/core/net_namespace.c:384 1 lock held by syz-executor/12262: #0: ffffffff8fcb2b10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-09710-ga1300691aed9 #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+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/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: 9530 Comm: kworker/u8:19 Not tainted 6.13.0-syzkaller-09710-ga1300691aed9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:ip6t_do_table+0xd1b/0x18a0 net/ipv6/netfilter/ip6_tables.c:321 Code: 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 f7 e8 a7 2a 79 f7 4d 03 26 eb 0d e8 9d 95 12 f7 48 8b 9c 24 a0 00 00 00 <48> 89 d8 48 c1 e8 03 49 be 00 00 00 00 00 fc ff df 42 0f b6 04 30 RSP: 0018:ffffc90000a17520 EFLAGS: 00000282 RAX: 1ffffffff1c6256b RBX: ffff8881b42357f0 RCX: dffffc0000000000 RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000008 RBP: ffffc90000a17708 R08: ffffffff8aacd6ac R09: 0000000000000000 R10: ffffc90000a17670 R11: fffff52000142ed2 R12: ffffe8ffffd98040 R13: 1ffff110023f1881 R14: ffffffff8e312b58 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005571a2e49088 CR3: 000000005914a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x62c/0x7c0 include/linux/netfilter.h:312 br_nf_post_routing+0xa20/0xe80 net/bridge/br_netfilter_hooks.c:969 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x2a7/0x460 include/linux/netfilter.h:312 br_forward_finish+0xd8/0x130 net/bridge/br_forward.c:66 br_nf_forward_finish+0xb49/0xfb0 net/bridge/br_netfilter_hooks.c:665 NF_HOOK+0x700/0x7c0 include/linux/netfilter.h:314 br_nf_forward_ip+0x61e/0x7b0 net/bridge/br_netfilter_hooks.c:719 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x2a7/0x460 include/linux/netfilter.h:312 __br_forward+0x489/0x660 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver+0xb3/0x150 net/bridge/br_forward.c:190 br_flood+0x2e4/0x680 net/bridge/br_forward.c:237 br_handle_frame_finish+0x18d2/0x2000 net/bridge/br_input.c:220 br_nf_hook_thresh+0x472/0x590 br_nf_pre_routing_finish_ipv6+0xaa0/0xdd0 NF_HOOK include/linux/netfilter.h:314 [inline] br_nf_pre_routing_ipv6+0x379/0x770 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:282 [inline] br_handle_frame+0x9f3/0x1530 net/bridge/br_input.c:433 __netif_receive_skb_core+0x13e7/0x4540 net/core/dev.c:5722 __netif_receive_skb_one_core net/core/dev.c:5826 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:5941 process_backlog+0x662/0x15b0 net/core/dev.c:6289 __napi_poll+0xcb/0x490 net/core/dev.c:7106 napi_poll net/core/dev.c:7175 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7297 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 do_softirq+0x11b/0x1e0 kernel/softirq.c:462 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:389 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x312/0x3b0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x328/0x610 net/batman-adv/network-coding.c:720 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244