syzbot

INFO: task syz.1.1546:5278 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1546      state:D stack:0     pid:5278  tgid:5276  ppid:288    flags:0x00004006
Call Trace:
 <TASK>
 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
 rcu_barrier+0x4d/0x530 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+0x383/0x410 arch/x86/kvm/x86.c:12898
 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline]
 kvm_put_kvm+0xb04/0x12b0 virt/kvm/kvm_main.c:1391
 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1414
 __fput+0x1fe/0xa00 fs/file_table.c:429
 ____fput+0x20/0x30 fs/file_table.c:457
 task_work_run+0x1e3/0x250 kernel/task_work.c:240
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0x9bc/0x2630 kernel/exit.c:953
 do_group_exit+0x22a/0x300 kernel/exit.c:1095
 get_signal+0x139d/0x14f0 kernel/signal.c:2933
 arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [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+0x58/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7ff71358ebe9
RSP: 002b:00007ff7143ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007ff7137c5fa0 RCX: 00007ff71358ebe9
RDX: 0000200000000040 RSI: 000000004020ae46 RDI: 000000000000000b
RBP: 00007ff713611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff7137c6038 R14: 00007ff7137c5fa0 R15: 00007fff29204708
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 3aa8e93a75ec4fb080c21ea51d8727149e6cfac5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 __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
 </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 3aa8e93a75ec4fb080c21ea51d8727149e6cfac5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:stack_trace_consume_entry+0x133/0x2a0 kernel/stacktrace.c:94
Code: cb e8 b1 d5 67 00 49 89 d9 4d 89 e0 4c 89 f2 48 8b 75 c0 49 89 37 41 8b 18 41 0f b6 44 15 00 84 c0 0f 85 42 01 00 00 41 3b 19 <0f> 92 c0 48 83 c4 20 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc
RSP: 0018:ffffc900000071f0 EFLAGS: 00000283
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000007200
RDX: dffffc0000000000 RSI: ffffffff81d7e601 RDI: ffffc90000007300
RBP: ffffc90000007238 R08: ffffc90000007310 R09: ffffc90000007308
R10: 0000000000000003 R11: ffffffff81744330 R12: ffffc9000000730c
R13: 1ffff92000000e61 R14: ffffc90000007380 R15: ffffc90000007398
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557213693b90 CR3: 00000000072a8000 CR4: 00000000003526b0
Call Trace:
 <IRQ>
 arch_stack_walk+0x12d/0x170 arch/x86/kernel/stacktrace.c:27
 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_noprof+0x131/0x3a0 mm/slub.c:4227
 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:245
 br_handle_frame_finish+0x12bb/0x1720 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+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
 </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+0x5c6/0xd20 kernel/rcu/tree.c:2594
 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
 rcu_nocb_cb_kthread+0x4dc/0xac0 kernel/rcu/tree_nocb.h:957
 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
 </TASK>
net_ratelimit: 63661 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 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:ca:e3:b3:52:a6:f3, 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:ca:e3:b3:52:a6:f3, 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:ca:e3:b3:52:a6:f3, vlan:0)
net_ratelimit: 90546 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:ca:e3:b3:52:a6:f3, 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:ca:e3:b3:52:a6:f3, 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:ca:e3:b3:52:a6:f3, 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)