INFO: task syz.2.1970:6503 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1970 state:D stack:0 pid:6503 tgid:6503 ppid:290 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:6016 [inline]
__schedule+0x1399/0x1fa0 kernel/sched/core.c:7870
__schedule_loop kernel/sched/core.c:7951 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7966
schedule_timeout+0xc7/0x3b0 kernel/time/timer.c:2596
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0x369/0x650 kernel/sched/completion.c:127
wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
__flush_work+0x712/0xb10 kernel/workqueue.c:4233
__cancel_work_sync kernel/workqueue.c:4354 [inline]
cancel_work_sync+0xac/0xe0 kernel/workqueue.c:4391
uhid_dev_destroy drivers/hid/uhid.c:584 [inline]
uhid_char_release+0xa7/0x600 drivers/hid/uhid.c:662
__fput+0x1fe/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e8/0x260 kernel/task_work.c:246
resume_user_mode_work+0x35/0x50 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x63/0xb0 kernel/entry/common.c:218
do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f1216d9c819
RSP: 002b:00007fffd2208a98 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fffd2208b80 RCX: 00007f1216d9c819
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000041603 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2e020000 R11: 0000000000000246 R12: 00007fffd2208bc0
R13: 00007f1217015fac R14: 0000000000041663 R15: 00007f1217015fa0
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 3c3e934d31ea577738626f5044e1400ec85c2ff3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
__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+0x2c6/0x370 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 3c3e934d31ea577738626f5044e1400ec85c2ff3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:438 [inline]
RIP: 0010:find_match+0x100/0x10e0 net/ipv6/route.c:781
Code: 00 00 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 0f 85 14 0c 00 00 8b 1b 31 ff 89 de e8 40 48 8e fc <85> db 74 54 e8 f7 43 8e fc 41 80 e7 10 41 0f b6 df 31 ff 89 de e8
RSP: 0018:ffffc900000071f8 EFLAGS: 00000246
RAX: ffffffff84f968b0 RBX: 0000000000000000 RCX: 0000000000000100
RDX: ffff888103661300 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900000072b0 R08: ffffc90000007540 R09: ffffc90000007550
R10: ffffc900000076b0 R11: fffff52000000eda R12: 0000000000000001
R13: 1ffff11021d64218 R14: 0000000000000003 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe6e4b47e20 CR3: 000000010c700000 CR4: 00000000003526b0
Call Trace:
__find_rr_leaf+0x24e/0x840 net/ipv6/route.c:869
find_rr_leaf net/ipv6/route.c:890 [inline]
rt6_select net/ipv6/route.c:934 [inline]
fib6_table_lookup+0x2ee/0x9e0 net/ipv6/route.c:2241
ip6_pol_route+0x17a/0x1360 net/ipv6/route.c:2277
ip6_pol_route_input+0x5a/0x80 net/ipv6/route.c:2334
pol_lookup_func include/net/ip6_fib.h:626 [inline]
fib6_rule_lookup+0x4ee/0x6d0 net/ipv6/fib6_rules.c:117
ip6_route_input_lookup net/ipv6/route.c:2346 [inline]
ip6_route_input+0x62e/0x8f0 net/ipv6/route.c:2642
ip6_rcv_finish_core net/ipv6/ip6_input.c:66 [inline]
ip6_rcv_finish+0x15a/0x3e0 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:5776 [inline]
__netif_receive_skb net/core/dev.c:5889 [inline]
process_backlog+0x44b/0xad0 net/core/dev.c:6225
__napi_poll+0xd0/0x610 net/core/dev.c:6876
napi_poll net/core/dev.c:6945 [inline]
net_rx_action+0x5ea/0xd80 net/core/dev.c:7067
handle_softirqs+0x1ad/0x630 kernel/softirq.c:621
__do_softirq+0xf/0x16 kernel/softirq.c:659
do_softirq+0xb8/0x110 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+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+0x2c6/0x370 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: 174530 callbacks suppressed
ICMPv6: NA: aa:aa:aa:aa:aa:0c advertised our address fe80::a8aa:aaff:feaa:aa0c on bridge0!
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 veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
ICMPv6: NA: aa:aa:aa:aa:aa:0c advertised our address fe80::a8aa:aaff:feaa:aa0c on bridge0!
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 veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
ICMPv6: NA: aa:aa:aa:aa:aa:0c advertised our address fe80::a8aa:aaff:feaa:aa0c on bridge0!
net_ratelimit: 168205 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:0c, vlan:0)
ICMPv6: NA: aa:aa:aa:aa:aa:0c advertised our address fe80::a8aa:aaff:feaa:aa0c on bridge0!
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: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)
ICMPv6: NA: aa:aa:aa:aa:aa:0c advertised our address fe80::a8aa:aaff:feaa:aa0c on bridge0!
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 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:0c, vlan:0)