INFO: task kworker/u8:1:13 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:1 state:D stack:0 pid:13 tgid:13 ppid:2 flags:0x00004000
Workqueue: events_unbound linkwatch_event
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
linkwatch_event+0x12/0x60 net/core/link_watch.c:285
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d5/0x1020 kernel/workqueue.c:3319
worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
kthread+0x2c7/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
INFO: task kworker/u8:4:3862 blocked for more than 124 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4 state:D stack:0 pid:3862 tgid:3862 ppid:2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
addrconf_verify_work+0x1d/0x50 net/ipv6/addrconf.c:4775
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d5/0x1020 kernel/workqueue.c:3319
worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
kthread+0x2c7/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 26040f0ed9382bf65720d717d6d6db2d10869199
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
dump_stack+0x19/0x20 lib/dump_stack.c:129
nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
watchdog+0xd8f/0xed0 kernel/hung_task.c:423
kthread+0x2c7/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 26040f0ed9382bf65720d717d6d6db2d10869199
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:unwind_next_frame+0x34e/0x750 arch/x86/kernel/unwind_frame.c:273
Code: c0 74 27 41 80 3c 16 00 74 0e 4c 89 ef 49 89 c6 e8 f7 0f 98 00 4c 89 f0 49 c7 45 00 00 00 00 00 4c 8b 75 d0 4c 8b 6d c0 eb 65 <4d> 85 e4 74 27 49 83 c4 20 4c 89 e0 48 c1 e8 03 80 3c 10 00 4c 8b
RSP: 0018:ffffc90000006f28 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc90000006fa8 RCX: 0000000000006f00
RDX: dffffc0000000000 RSI: ffffffff846fb217 RDI: ffffc90000147f48
RBP: ffffc90000006f98 R08: ffffc90000007070 R09: ffffc90000007068
R10: 0000000000000009 R11: ffffffff817441e0 R12: 0000000000000000
R13: ffffc90000006ff8 R14: 1ffff92000000dff R15: ffffc90000007630
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557db969eb98 CR3: 000000010b38a000 CR4: 00000000003526b0
Call Trace:
arch_stack_walk+0x139/0x170 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9d/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:69
kasan_save_free_info+0x4a/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:248 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:265
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2418 [inline]
slab_free mm/slub.c:4672 [inline]
kmem_cache_free+0x1c1/0x510 mm/slub.c:4779
kfree_skbmem net/core/skbuff.c:-1 [inline]
__kfree_skb+0x18f/0x210 net/core/skbuff.c:1203
sk_skb_reason_drop+0xd8/0x310 net/core/skbuff.c:1240
kfree_skb_reason include/linux/skbuff.h:1271 [inline]
kfree_skb include/linux/skbuff.h:1280 [inline]
ip6_mc_input+0x4f3/0x670 net/ipv6/ip6_input.c:587
dst_input include/net/dst.h:469 [inline]
ip6_rcv_finish+0x341/0x3c0 net/ipv6/ip6_input.c:79
NF_HOOK include/linux/netfilter.h:317 [inline]
ipv6_rcv+0xed/0x220 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core net/core/dev.c:5757 [inline]
__netif_receive_skb net/core/dev.c:5870 [inline]
netif_receive_skb_internal net/core/dev.c:5956 [inline]
netif_receive_skb+0x147/0x7b0 net/core/dev.c:6015
br_netif_receive_skb net/bridge/br_input.c:30 [inline]
NF_HOOK include/linux/netfilter.h:317 [inline]
br_pass_frame_up+0x126/0x1c0 net/bridge/br_input.c:70
br_handle_frame_finish+0x12d9/0x1720 net/bridge/br_input.c:221
nf_hook_bridge_pre net/bridge/br_input.c:301 [inline]
br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424
__netif_receive_skb_core+0xf4b/0x3940 net/core/dev.c:5651
__netif_receive_skb_one_core net/core/dev.c:5755 [inline]
__netif_receive_skb net/core/dev.c:5870 [inline]
process_backlog+0x3e5/0xae0 net/core/dev.c:6206
__napi_poll+0xd3/0x610 net/core/dev.c:6857
napi_poll net/core/dev.c:6926 [inline]
net_rx_action+0x584/0xce0 net/core/dev.c:7048
handle_softirqs+0x1ab/0x630 kernel/softirq.c:621
__do_softirq+0xf/0x16 kernel/softirq.c:659
do_softirq+0xa6/0x100 kernel/softirq.c:503
__local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_do_batch+0x5c6/0xd20 kernel/rcu/tree.c:2594
nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
rcu_nocb_cb_kthread+0x4dc/0xac0 kernel/rcu/tree_nocb.h:957
kthread+0x2c7/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
net_ratelimit: 112254 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:d6:ce:28:8e:e0:7a, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:d6:ce:28:8e:e0:7a, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:d6:ce:28:8e:e0:7a, vlan:0)