INFO: task kworker/0:1:10 blocked for more than 126 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1 state:D stack:0 pid:10 tgid:10 ppid:2 flags:0x00004000
Workqueue: events fqdir_free_fn
Call Trace:
<TASK>
context_switch kernel/sched/core.c:6026 [inline]
__schedule+0x1399/0x1fa0 kernel/sched/core.c:7880
__schedule_loop kernel/sched/core.c:7961 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7976
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8033
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
rcu_barrier+0x4d/0x540 kernel/rcu/tree.c:4589
fqdir_free_fn+0x36/0x150 net/ipv4/inet_fragment.c:167
process_one_work kernel/workqueue.c:3261 [inline]
process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3342
worker_thread+0xc51/0x1370 kernel/workqueue.c:3423
kthread+0x2c9/0x370 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
</TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 8e204e40c44961bd6596aa96fc7bf4ad6280e2fe
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
<TASK>
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
dump_stack+0x19/0x20 lib/dump_stack.c:129
nmi_cpu_backtrace+0x2ba/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+0xdad/0xf00 kernel/hung_task.c:423
kthread+0x2c9/0x370 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
</TASK>
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 8e204e40c44961bd6596aa96fc7bf4ad6280e2fe
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:memcpy_orig+0xb9/0x150 arch/x86/lib/memcpy_64.S:126
Code: c2 20 48 29 d6 48 29 d7 83 fa 10 72 34 4c 8b 06 4c 8b 4e 08 4c 8b 54 16 f0 4c 8b 5c 16 f8 4c 89 07 4c 89 4f 08 4c 89 54 17 f0 <4c> 89 5c 17 f8 e9 0d 4e 02 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f
RSP: 0018:ffffc90000006d60 EFLAGS: 00000246
RAX: ffffc900000071bc RBX: 0000000000000010 RCX: ffffffff84f89b82
RDX: 0000000000000010 RSI: ffff888116b7df98 RDI: ffffc900000071bc
RBP: ffffc90000006d90 R08: 00000000000080fe R09: 1b00000000000000
R10: 00000000000080fe R11: 1b00000000000000 R12: 0000000000000000
R13: ffffffff84f89b82 R14: ffff888116b7df98 R15: ffffc900000071bc
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffeded06d4c CR3: 000000010af42000 CR4: 00000000003526b0
Call Trace:
<IRQ>
ip6_multipath_l3_keys+0x212/0x6d0 net/ipv6/route.c:2389
rt6_multipath_hash+0x3fb/0x15b0 net/ipv6/route.c:2527
ip6_route_input+0x75a/0x8f0 net/ipv6/route.c:2641
ip6_rcv_finish_core net/ipv6/ip6_input.c:66 [inline]
ip6_rcv_finish+0x15a/0x3c0 net/ipv6/ip6_input.c:77
NF_HOOK include/linux/netfilter.h:317 [inline]
ipv6_rcv+0xf1/0x240 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core net/core/dev.c:5789 [inline]
__netif_receive_skb net/core/dev.c:5902 [inline]
netif_receive_skb_internal net/core/dev.c:5988 [inline]
netif_receive_skb+0x147/0x7b0 net/core/dev.c:6047
br_netif_receive_skb net/bridge/br_input.c:30 [inline]
NF_HOOK include/linux/netfilter.h:317 [inline]
br_pass_frame_up+0x126/0x1b0 net/bridge/br_input.c:70
br_handle_frame_finish+0x120c/0x17a0 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+0xfae/0x3ab0 net/core/dev.c:5683
__netif_receive_skb_one_core net/core/dev.c:5787 [inline]
__netif_receive_skb net/core/dev.c:5902 [inline]
process_backlog+0x3e5/0xad0 net/core/dev.c:6238
__napi_poll+0xd0/0x610 net/core/dev.c:6889
napi_poll net/core/dev.c:6958 [inline]
net_rx_action+0x5ea/0xd80 net/core/dev.c:7080
handle_softirqs+0x1aa/0x630 kernel/softirq.c:621
__do_softirq+0xf/0x16 kernel/softirq.c:659
do_softirq+0xb8/0x110 kernel/softirq.c:503
</IRQ>
<TASK>
__local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_do_batch+0x5d9/0xd40 kernel/rcu/tree.c:2594
nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
rcu_nocb_cb_kthread+0x524/0xb30 kernel/rcu/tree_nocb.h:957
kthread+0x2c9/0x370 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
</TASK>
net_ratelimit: 118764 callbacks suppressed
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: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 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 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:42:36:32:52:a2:40, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
net_ratelimit: 124720 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:42:36:32:52:a2:40, 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:42:36:32:52:a2:40, 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:42:36:32:52:a2:40, 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)