INFO: task kworker/u8:2:46 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2 state:D stack:0 pid:46 tgid:46 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+0x64/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
INFO: task syz-executor:3087 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:3087 tgid:3087 ppid:1 flags:0x00004004
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
ip_tunnel_init_net+0x2f2/0x860 net/ipv4/ip_tunnel.c:1159
ipgre_init_net+0x28/0x30 net/ipv4/ip_gre.c:1063
ops_init+0x1b2/0x5d0 net/core/net_namespace.c:139
setup_net+0x20e/0x990 net/core/net_namespace.c:356
copy_net_ns+0x513/0xa30 net/core/net_namespace.c:510
create_new_namespaces+0x3b5/0x720 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x126/0x180 kernel/nsproxy.c:228
ksys_unshare+0x4fe/0x880 kernel/fork.c:3352
__do_sys_unshare kernel/fork.c:3423 [inline]
__se_sys_unshare kernel/fork.c:3421 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3421
x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fc35d1903e7
RSP: 002b:00007ffedb692d78 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fc35d3c5f40 RCX: 00007fc35d1903e7
RDX: 0000000000000005 RSI: 00007ffedb692c40 RDI: 0000000040000000
RBP: 00007fc35d3c67b8 R08: 00007fc35def7d60 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
INFO: task syz-executor:3091 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:3091 tgid:3091 ppid:1 flags:0x00004004
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
ip_tunnel_init_net+0x2f2/0x860 net/ipv4/ip_tunnel.c:1159
erspan_init_net+0x2d/0x40 net/ipv4/ip_gre.c:1760
ops_init+0x1b2/0x5d0 net/core/net_namespace.c:139
setup_net+0x20e/0x990 net/core/net_namespace.c:356
copy_net_ns+0x513/0xa30 net/core/net_namespace.c:510
create_new_namespaces+0x3b5/0x720 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x126/0x180 kernel/nsproxy.c:228
ksys_unshare+0x4fe/0x880 kernel/fork.c:3352
__do_sys_unshare kernel/fork.c:3423 [inline]
__se_sys_unshare kernel/fork.c:3421 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3421
x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fec60d903e7
RSP: 002b:00007ffe6308d268 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fec60fc5f40 RCX: 00007fec60d903e7
RDX: 0000000000000005 RSI: 00007ffe6308d130 RDI: 0000000040000000
RBP: 00007fec60fc67b8 R08: 00007fec61af7d60 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
INFO: task syz-executor:3093 blocked for more than 129 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:3093 tgid:3093 ppid:1 flags:0x00004004
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
ip_tunnel_init_net+0x2f2/0x860 net/ipv4/ip_tunnel.c:1159
ipip_init_net+0x2d/0x40 net/ipv4/ipip.c:601
ops_init+0x1b2/0x5d0 net/core/net_namespace.c:139
setup_net+0x20e/0x990 net/core/net_namespace.c:356
copy_net_ns+0x513/0xa30 net/core/net_namespace.c:510
create_new_namespaces+0x3b5/0x720 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x126/0x180 kernel/nsproxy.c:228
ksys_unshare+0x4fe/0x880 kernel/fork.c:3352
__do_sys_unshare kernel/fork.c:3423 [inline]
__se_sys_unshare kernel/fork.c:3421 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3421
x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f4bb5d903e7
RSP: 002b:00007ffe4e0fe6e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f4bb5fc5f40 RCX: 00007f4bb5d903e7
RDX: 0000000000000005 RSI: 00007ffe4e0fe5b0 RDI: 0000000040000000
RBP: 00007f4bb5fc67b8 R08: 00007f4bb6af7d60 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
INFO: task syz-executor:3094 blocked for more than 130 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:3094 tgid:3094 ppid:1 flags:0x00004004
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
ip_tunnel_init_net+0x2f2/0x860 net/ipv4/ip_tunnel.c:1159
erspan_init_net+0x2d/0x40 net/ipv4/ip_gre.c:1760
ops_init+0x1b2/0x5d0 net/core/net_namespace.c:139
setup_net+0x20e/0x990 net/core/net_namespace.c:356
copy_net_ns+0x513/0xa30 net/core/net_namespace.c:510
create_new_namespaces+0x3b5/0x720 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x126/0x180 kernel/nsproxy.c:228
ksys_unshare+0x4fe/0x880 kernel/fork.c:3352
__do_sys_unshare kernel/fork.c:3423 [inline]
__se_sys_unshare kernel/fork.c:3421 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3421
x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7eff8ab903e7
RSP: 002b:00007ffc04c2cc18 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007eff8adc5f40 RCX: 00007eff8ab903e7
RDX: 0000000000000005 RSI: 00007ffc04c2cae0 RDI: 0000000040000000
RBP: 00007eff8adc67b8 R08: 00007eff8b8f7d60 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 e0010524de270d562e17ec59754923f7dbe680d3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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+0x64/0xa0 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: 13 Comm: kworker/u8:1 Not tainted syzkaller #0 e0010524de270d562e17ec59754923f7dbe680d3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: netns cleanup_net
RIP: 0010:unwind_get_return_address+0x64/0x90 arch/x86/kernel/unwind_frame.c:19
Code: 43 80 3c 37 00 74 08 48 89 df e8 87 f3 97 00 48 8b 3b e8 1f 13 13 00 85 c0 74 14 43 80 3c 37 00 74 08 48 89 df e8 6c f3 97 00 <48> 8b 03 eb 02 31 c0 5b 41 5e 41 5f 5d c3 cc cc cc cc cc 89 d9 80
RSP: 0018:ffffc90000007140 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc900000071b0 RCX: 0000000000007100
RDX: ffffc900000d7801 RSI: 1ffff92000000e2e RDI: ffffffff8470d8a2
RBP: ffffc90000007158 R08: ffffc90000007230 R09: ffffc90000007228
R10: 0000000000000016 R11: ffffffff81744330 R12: ffff888103650000
R13: 0000000000082820 R14: dffffc0000000000 R15: 1ffff92000000e36
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055fbfc60db98 CR3: 000000010c3b0000 CR4: 00000000003526b0
Call Trace:
arch_stack_walk+0x10b/0x170 arch/x86/kernel/stacktrace.c:26
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_alloc_info+0x40/0x50 mm/kasan/generic.c:565
unpoison_slab_object mm/kasan/common.c:320 [inline]
__kasan_slab_alloc+0x73/0x90 mm/kasan/common.c:346
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4169 [inline]
slab_alloc_node mm/slub.c:4218 [inline]
kmem_cache_alloc_node_noprof+0x139/0x3b0 mm/slub.c:4272
kmalloc_reserve+0xcf/0x500 net/core/skbuff.c:596
__alloc_skb+0x144/0x370 net/core/skbuff.c:687
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+0x39c/0x1720 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+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
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock_bh+0x54/0x60 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:396 [inline]
addrconf_ifdown+0x608/0x1940 net/ipv6/addrconf.c:3951
addrconf_notify+0x17a/0xea0 net/ipv6/addrconf.c:-1
notifier_call_chain+0x10e/0x2c0 kernel/notifier.c:93
raw_notifier_call_chain+0x31/0x40 kernel/notifier.c:461
call_netdevice_notifiers_info net/core/dev.c:2067 [inline]
call_netdevice_notifiers_extack net/core/dev.c:2105 [inline]
call_netdevice_notifiers net/core/dev.c:2119 [inline]
unregister_netdevice_many_notify+0xe32/0x1bd0 net/core/dev.c:11489
unregister_netdevice_many net/core/dev.c:11551 [inline]
default_device_exit_batch+0x810/0x8a0 net/core/dev.c:12034
ops_exit_list net/core/net_namespace.c:178 [inline]
cleanup_net+0x72e/0xc70 net/core/net_namespace.c:642
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+0x64/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244