INFO: task kworker/u8:0:12 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:0 state:D stack:0 pid:12 tgid:12 ppid:2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
__schedule_loop kernel/sched/core.c:7924 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7939
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996
__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
rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
addrconf_dad_work+0xce/0x1530 net/ipv6/addrconf.c:4234
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319
worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400
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
INFO: task syz-executor:461 blocked for more than 123 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:461 tgid:461 ppid:1 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
__schedule_loop kernel/sched/core.c:7924 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7939
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996
__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
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672
netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x718/0x790 net/socket.c:2217
__do_sys_sendto net/socket.c:2229 [inline]
__se_sys_sendto net/socket.c:2225 [inline]
__x64_sys_sendto+0xe9/0x100 net/socket.c:2225
x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f54d8b560d7
RSP: 002b:00007fff33d50fb0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055557cc2d500 RCX: 00007f54d8b560d7
RDX: 000000000000002c RSI: 00007f54d9944670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff33d51014 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f54d9944670 R15: 0000000000000000
INFO: task syz-executor:463 blocked for more than 124 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:463 tgid:463 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
__schedule_loop kernel/sched/core.c:7924 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7939
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996
__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
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672
netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x718/0x790 net/socket.c:2217
__do_sys_sendto net/socket.c:2229 [inline]
__se_sys_sendto net/socket.c:2225 [inline]
__x64_sys_sendto+0xe9/0x100 net/socket.c:2225
x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fefaa7560d7
RSP: 002b:00007ffc32c8d780 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000555591eac500 RCX: 00007fefaa7560d7
RDX: 0000000000000028 RSI: 00007fefab544670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffc32c8d7e4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fefab544670 R15: 0000000000000000
INFO: task syz-executor:466 blocked for more than 125 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:466 tgid:466 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
__schedule_loop kernel/sched/core.c:7924 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7939
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996
__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
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672
netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x718/0x790 net/socket.c:2217
__do_sys_sendto net/socket.c:2229 [inline]
__se_sys_sendto net/socket.c:2225 [inline]
__x64_sys_sendto+0xe9/0x100 net/socket.c:2225
x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fab6f5560d7
RSP: 002b:00007ffc9c22a7e0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00005555733de500 RCX: 00007fab6f5560d7
RDX: 0000000000000028 RSI: 00007fab70344670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffc9c22a844 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fab70344670 R15: 0000000000000000
INFO: task syz-executor:467 blocked for more than 126 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:467 tgid:467 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
__schedule_loop kernel/sched/core.c:7924 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7939
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996
__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
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672
netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x718/0x790 net/socket.c:2217
__do_sys_sendto net/socket.c:2229 [inline]
__se_sys_sendto net/socket.c:2225 [inline]
__x64_sys_sendto+0xe9/0x100 net/socket.c:2225
x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f86119560d7
RSP: 002b:00007fffb7fd31f0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00005555787d1500 RCX: 00007f86119560d7
RDX: 0000000000000028 RSI: 00007f8612744670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fffb7fd3254 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f8612744670 R15: 0000000000000000
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 d2070f6ccd239e5a47ec9c1c2f682235c3170fcc
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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+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
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 d2070f6ccd239e5a47ec9c1c2f682235c3170fcc
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:list_empty include/linux/list.h:373 [inline]
RIP: 0010:___rmqueue_pcplist+0x287/0x31b0 mm/page_alloc.c:3214
Code: 48 89 84 24 18 01 00 00 4c 89 8c 24 b0 00 00 00 49 6b c1 68 48 89 44 24 20 4c 89 7c 24 78 4c 89 fb 48 c1 eb 03 42 80 3c 2b 00 <74> 08 4c 89 ff e8 af b3 05 00 49 8b 07 4c 39 f8 0f 84 1e 01 00 00
RSP: 0018:ffffc9000022fd60 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff1103edee454 RCX: ffffffff8635a480
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff87e37c00
RBP: ffffc9000022ffd0 R08: ffff8881f6f72280 R09: 0000000000000000
R10: 0000000000000000 R11: 00000000ffffffff R12: ffff8881f6f722a0
R13: dffffc0000000000 R14: ffff8881f6f72280 R15: ffff8881f6f722a0
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5d44b45000 CR3: 000000011f8c4000 CR4: 00000000003526b0
Call Trace:
__rmqueue_pcplist mm/page_alloc.c:3263 [inline]
rmqueue_pcplist mm/page_alloc.c:3292 [inline]
rmqueue mm/page_alloc.c:3325 [inline]
get_page_from_freelist+0x6f5/0x4a20 mm/page_alloc.c:3911
__alloc_pages_noprof+0x35f/0x7e0 mm/page_alloc.c:5264
alloc_slab_page+0x6b/0x1e0 mm/slub.c:-1
allocate_slab+0x69/0x420 mm/slub.c:2687
new_slab mm/slub.c:2741 [inline]
___slab_alloc+0x5a2/0x8d0 mm/slub.c:3934
__slab_alloc mm/slub.c:4025 [inline]
__slab_alloc_node mm/slub.c:4078 [inline]
slab_alloc_node mm/slub.c:4239 [inline]
kmem_cache_alloc_node_noprof+0x29b/0x420 mm/slub.c:4305
__alloc_skb+0x108/0x370 net/core/skbuff.c:677
alloc_skb include/linux/skbuff.h:1331 [inline]
nlmsg_new include/net/netlink.h:1015 [inline]
fdb_notify+0x78/0x150 net/bridge/br_fdb.c:195
br_fdb_update+0x4b7/0x680 net/bridge/br_fdb.c:941
br_handle_frame_finish+0x3a3/0x1760 net/bridge/br_input.c:141
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:5657
__netif_receive_skb_one_core net/core/dev.c:5761 [inline]
__netif_receive_skb net/core/dev.c:5876 [inline]
process_backlog+0x3e5/0xad0 net/core/dev.c:6212
__napi_poll+0xd3/0x610 net/core/dev.c:6863
napi_poll net/core/dev.c:6932 [inline]
net_rx_action+0x5ea/0xd80 net/core/dev.c:7054
handle_softirqs+0x1aa/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+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