INFO: task kworker/0:3:502 blocked for more than 126 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:3 state:D stack:0 pid:502 tgid:502 ppid:2 flags:0x00004000
Workqueue: events fqdir_free_fn
Call Trace:
<TASK>
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_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
rcu_barrier+0x415/0x540 kernel/rcu/tree.c:4657
fqdir_free_fn+0x36/0x150 net/ipv4/inet_fragment.c:167
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
</TASK>
INFO: task syz.2.6425:13487 blocked for more than 127 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.6425 state:D stack:0 pid:13487 tgid:13487 ppid:323 flags:0x00004004
Call Trace:
<TASK>
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
rcu_barrier+0x4d/0x540 kernel/rcu/tree.c:4589
kvm_mmu_uninit_tdp_mmu+0x1df/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51
kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6572
kvm_arch_destroy_vm+0x398/0x420 arch/x86/kvm/x86.c:12961
kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline]
kvm_put_kvm+0xb04/0x12c0 virt/kvm/kvm_main.c:1392
kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415
__fput+0x1fb/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e5/0x260 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: 0033:0x7f95df39bf79
RSP: 002b:00007ffd74432358 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffd74432440 RCX: 00007f95df39bf79
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 000000000003e193 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2ff20000 R11: 0000000000000246 R12: 00007ffd74432480
R13: 00007f95df615fac R14: 000000000003e1fc R15: 00007f95df615fa0
</TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 aad5f479f94818aba7ed2ddeb7ace07d386963b4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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: 33 Comm: rcuop/1 Not tainted syzkaller #0 aad5f479f94818aba7ed2ddeb7ace07d386963b4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:update_stack_state+0x2b0/0x4b0 arch/x86/kernel/unwind_frame.c:261
Code: f7 e8 04 9e 9a 00 49 83 3e 00 74 2b 44 3b 6d ac 75 25 48 8b 45 a0 48 39 45 b0 73 1b 31 db 89 d8 48 81 c4 98 00 00 00 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 4c 8b 6d 80 4d 85 ed 4c 89
RSP: 0018:ffffc90000007160 EFLAGS: 00000296
RAX: 0000000000007201 RBX: ffffc90000007208 RCX: ffffc90000007901
RDX: ffffc90000007950 RSI: 1ffff92000000e42 RDI: ffffc90000007260
RBP: ffffc90000007178 R08: ffffc900000072d0 R09: ffffc900000072c8
R10: 0000000000000007 R11: ffffffff8175cba0 R12: 0000000000000000
R13: ffffc90000007230 R14: ffffc90000007248 R15: 1ffff92000000e49
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f072c4fcbfe CR3: 000000010c3b8000 CR4: 00000000003526b0
Call Trace:
<IRQ>
unwind_next_frame+0x3c1/0x750 arch/x86/kernel/unwind_frame.c:315
arch_stack_walk+0x138/0x170 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:49 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:70
kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:565
unpoison_slab_object mm/kasan/common.c:321 [inline]
__kasan_slab_alloc+0x73/0x90 mm/kasan/common.c:347
kasan_slab_alloc include/linux/kasan.h:251 [inline]
slab_post_alloc_hook mm/slub.c:4202 [inline]
slab_alloc_node mm/slub.c:4251 [inline]
kmem_cache_alloc_noprof+0x1bf/0x410 mm/slub.c:4260
skb_clone+0x229/0x460 net/core/skbuff.c:2082
deliver_clone net/bridge/br_forward.c:125 [inline]
br_flood+0x661/0x730 net/bridge/br_forward.c:246
br_handle_frame_finish+0x12f9/0x1760 net/bridge/br_input.c:215
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+0xfb1/0x3ab0 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
</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: 239572 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:fe:04:e9:7a:e3, 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)
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)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:fe:04:e9:7a:e3, 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: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)
net_ratelimit: 272080 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 veth0_to_bridge with own address as source address (addr:fe:fe:04:e9:7a:e3, 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: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)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:fe:fe:04:e9:7a:e3, 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:0c, vlan:0)