INFO: task kworker/0:1:10 blocked for more than 143 seconds.
Tainted: G U L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1 state:D stack:25016 pid:10 tgid:10 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: events switchdev_deferred_process_work
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc69/0x1ca0 kernel/locking/mutex.c:776
switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
INFO: task kworker/u10:8:18313 blocked for more than 143 seconds.
Tainted: G U L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u10:8 state:D stack:25480 pid:18313 tgid:18313 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc69/0x1ca0 kernel/locking/mutex.c:776
rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4734
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Showing all locks held in the system:
3 locks held by kworker/0:1/10:
#0: ffff88813ff55948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc900000f7c90 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
1 lock held by khungtaskd/31:
#0: ffffffff8e3c94a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c94a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c94a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
1 lock held by khugepaged/38:
#0: ffffffff8e506548 (lock#5){+.+.}-{4:4}, at: __lru_add_drain_all+0x6e/0x6f0 mm/swap.c:840
3 locks held by kworker/0:2/117:
2 locks held by getty/5588:
#0: ffff88814cac10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x1510 drivers/tty/n_tty.c:2211
4 locks held by syz-executor/5816:
#0: ffff88802a265088 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x117/0x580 mm/mmap_lock.c:259
#1: ffff888035892518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x174/0x380 mm/memory.c:3528
#2: ffff888078602c00 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1092 [inline]
#2: ffff888078602c00 (mapping.invalidate_lock#2){++++}-{4:4}, at: ext4_page_mkwrite+0x353/0x1880 fs/ext4/inode.c:6670
#3: ffff8880786028f0 (&ei->i_data_sem){++++}-{4:4}, at: ext4_da_map_blocks fs/ext4/inode.c:1961 [inline]
#3: ffff8880786028f0 (&ei->i_data_sem){++++}-{4:4}, at: ext4_da_get_block_prep+0x6ad/0x1230 fs/ext4/inode.c:2027
3 locks held by kworker/0:5/5891:
3 locks held by kworker/1:6/5911:
#0: ffff88813ff56948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc9000441fc90 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x91/0x1190 net/wireless/reg.c:2453
4 locks held by kworker/1:7/5923:
#0: ffff88805dff7148 ((wq_completion)wg-kex-wg1#13){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc90004d1fc90 ((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+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffff8880358c5308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x880 drivers/net/wireguard/noise.c:598
#3: ffff88807fa94890 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x880 drivers/net/wireguard/noise.c:632
4 locks held by kworker/0:8/7412:
6 locks held by kworker/u10:2/9829:
3 locks held by kworker/u10:9/9916:
2 locks held by kworker/u10:14/9998:
3 locks held by kworker/u10:20/10004:
6 locks held by kworker/u10:21/10005:
4 locks held by kworker/u10:29/11842:
4 locks held by kworker/u10:41/11857:
#0: ffff8880833ce948 ((wq_completion)wg-kex-wg1#9){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc90005007c90 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffff8880213b9308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0xec/0x610 drivers/net/wireguard/noise.c:529
#3: ffff88805e5af030 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x100/0x610 drivers/net/wireguard/noise.c:530
3 locks held by kworker/0:3/16995:
2 locks held by kworker/0:6/17710:
1 lock held by syz-executor/17909:
#0: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3436
3 locks held by kworker/u10:8/18313:
#0: ffff88814ca8b148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc90005117c90 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4734
6 locks held by kworker/u10:12/18316:
1 lock held by syz.2.2491/18464:
#0: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3436
1 lock held by syz.3.2554/18748:
#0: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3436
4 locks held by kworker/u10:26/19269:
#0: ffff88814d4d5148 ((wq_completion)ext4-rsv-conversion){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc9000bb1fc90 ((work_completion)(&ei->i_rsv_conversion_work)){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffff888035896950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x5e7/0x1410 fs/jbd2/transaction.c:444
#3: ffff8880786028f0 (&ei->i_data_sem){++++}-{4:4}, at: ext4_map_blocks+0x475/0x1350 fs/ext4/inode.c:815
2 locks held by kworker/u10:34/19270:
3 locks held by kworker/u10:43/19271:
4 locks held by kworker/u10:44/19272:
3 locks held by kworker/u10:45/19273:
4 locks held by kworker/u10:46/19274:
3 locks held by kworker/u10:47/19275:
3 locks held by kworker/u10:48/19276:
1 lock held by syz.3.3354/22459:
#0: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: ppp_release+0x167/0x230 drivers/net/ppp/ppp_generic.c:413
1 lock held by syz.1.3569/23441:
#0: ffffffff90144f68 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x612/0x4880 drivers/net/tun.c:3078
4 locks held by kworker/0:13/23466:
#0: ffff88805dff7148 ((wq_completion)wg-kex-wg1#13){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc90005147c90 ((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+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffff8880358c5308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x880 drivers/net/wireguard/noise.c:598
#3: ffff88807fa94890 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x880 drivers/net/wireguard/noise.c:632
3 locks held by kworker/0:14/23468:
2 locks held by dhcpcd/23480:
#0: ffff88805c9063c8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
#0: ffff88805c9063c8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:661
#1: ffffffff8e3d4bf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
2 locks held by dhcpcd/23481:
#0: ffff88805c904cc8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
#0: ffff88805c904cc8 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:661
#1: ffffffff8e3d4bf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by dhcpcd/23482:
#0: ffff88805c902a48 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
#0: ffff88805c902a48 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:661
1 lock held by dhcpcd/23483:
#0: ffff88805c903008 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
#0: ffff88805c903008 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:661
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U L syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x133/0x180 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xe66/0x1180 kernel/hung_task.c:515
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9999 Comm: kworker/u10:15 Tainted: G U L syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:453 [inline]
RIP: 0010:find_match+0x194/0x15d0 net/ipv6/route.c:780
Code: 12 48 a0 f7 4d 85 ff 74 4c e8 08 48 a0 f7 49 8d bf 58 06 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 13 11 00 00 45
RSP: 0000:ffffc900000068e8 EFLAGS: 00000a02
RAX: dffffc0000000000 RBX: 0000000000000003 RCX: ffffffff8a1e12c2
RDX: 0000000000000000 RSI: ffffffff8a1e10b8 RDI: ffff888035540658
RBP: ffffc900000069f0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: ffff88802d0a66b0 R12: ffff88805e32e4df
R13: ffff88805e32e4c8 R14: 1ffff92000000d2c R15: ffff888035540000
FS: 0000000000000000(0000) GS:ffff8881248fd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f9abff8 CR3: 000000000e184000 CR4: 00000000003526f0
Call Trace:
__find_rr_leaf+0x140/0xe00 net/ipv6/route.c:868
find_rr_leaf net/ipv6/route.c:889 [inline]
rt6_select net/ipv6/route.c:933 [inline]
fib6_table_lookup+0x57c/0xa30 net/ipv6/route.c:2233
ip6_pol_route+0x1cc/0x1230 net/ipv6/route.c:2269
pol_lookup_func include/net/ip6_fib.h:617 [inline]
fib6_rule_lookup+0x536/0x720 net/ipv6/fib6_rules.c:120
ip6_route_input_lookup net/ipv6/route.c:2338 [inline]
ip6_route_input+0x662/0xc70 net/ipv6/route.c:2641
ip6_rcv_finish_core.constprop.0+0x1a0/0x5d0 net/ipv6/ip6_input.c:66
ip6_rcv_finish+0x130/0x580 net/ipv6/ip6_input.c:77
ip_sabotage_in+0x21e/0x290 net/bridge/br_netfilter_hooks.c:990
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623
nf_hook.constprop.0+0x424/0x750 include/linux/netfilter.h:273
NF_HOOK include/linux/netfilter.h:316 [inline]
ipv6_rcv+0xa4/0x650 net/ipv6/ip6_input.c:311
__netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6137
__netif_receive_skb+0x1d/0x160 net/core/dev.c:6250
netif_receive_skb_internal net/core/dev.c:6336 [inline]
netif_receive_skb+0x137/0x760 net/core/dev.c:6395
NF_HOOK include/linux/netfilter.h:318 [inline]
NF_HOOK include/linux/netfilter.h:312 [inline]
br_pass_frame_up+0x346/0x490 net/bridge/br_input.c:70
br_handle_frame_finish+0x10e8/0x1f00 net/bridge/br_input.c:235
br_nf_hook_thresh+0x307/0x410 net/bridge/br_netfilter_hooks.c:1167
br_nf_pre_routing_finish_ipv6+0x76a/0xfc0 net/bridge/br_netfilter_ipv6.c:154
NF_HOOK include/linux/netfilter.h:318 [inline]
br_nf_pre_routing_ipv6+0x3cd/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:158 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
br_handle_frame+0xb28/0x14e0 net/bridge/br_input.c:442
__netif_receive_skb_core.constprop.0+0x6b3/0x35b0 net/core/dev.c:6024
__netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6135
__netif_receive_skb+0x1d/0x160 net/core/dev.c:6250
process_backlog+0x4a2/0x1650 net/core/dev.c:6602
__napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7666
napi_poll net/core/dev.c:7729 [inline]
net_rx_action+0x9f9/0xfa0 net/core/dev.c:7881
handle_softirqs+0x219/0x950 kernel/softirq.c:622
do_softirq kernel/softirq.c:523 [inline]
do_softirq+0xb2/0xf0 kernel/softirq.c:510
__local_bh_enable_ip+0x100/0x120 kernel/softirq.c:450
spin_unlock_bh include/linux/spinlock.h:396 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:890 [inline]
nsim_dev_trap_report_work+0x8b5/0xcf0 drivers/net/netdevsim/dev.c:921
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246