INFO: task syz.3.1335:4490 blocked for more than 123 seconds. Not tainted 6.12.38-syzkaller-g735ed21f0480 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.1335 state:D stack:0 pid:4490 tgid:4489 ppid:952 flags:0x00004006 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_timeout+0xb2/0x3a0 kernel/time/timer.c:2595 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common+0x359/0x630 kernel/sched/completion.c:127 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148 rcu_barrier+0x415/0x530 kernel/rcu/tree.c:4657 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+0x1e0/0x250 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: 0033:0x7fc440f8ebe9 RSP: 002b:00007fc441e560e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007fc4411b5fa8 RCX: 00007fc440f8ebe9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fc4411b5fac RBP: 00007fc4411b5fa0 R08: 7fffffffffffffff R09: 0000000000000000 R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc4411b6038 R14: 00007ffd8c7bd760 R15: 00007ffd8c7bd848 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.38-syzkaller-g735ed21f0480 #0 22d9d5446b80d45600909e55ac0a2e2bc548e6b2 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+0x2ca/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: 4510 Comm: syz-executor Not tainted 6.12.38-syzkaller-g735ed21f0480 #0 22d9d5446b80d45600909e55ac0a2e2bc548e6b2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:unwind_get_return_address+0x3a/0x90 arch/x86/kernel/unwind_frame.c:19 Code: 49 be 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 4d 83 3b 00 74 3a 48 83 c3 48 49 89 df 49 c1 ef 03 <43> 80 3c 37 00 74 08 48 89 df e8 67 e9 97 00 48 8b 3b e8 7f 12 13 RSP: 0018:ffffc900000071a0 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffffc90000007210 RCX: 0000000000007201 RDX: ffffc900000078d0 RSI: 1ffff92000000e3a RDI: ffffc900000071c8 RBP: ffffc900000071b8 R08: ffffc90000007290 R09: ffffc90000007288 R10: 0000000000000007 R11: ffffffff81743d30 R12: ffff8881178b9300 R13: 0000000000000820 R14: dffffc0000000000 R15: 1ffff92000000e42 FS: 000055555a201500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1330ae7d60 CR3: 0000000146a80000 CR4: 00000000003526b0 DR0: 0000000000000000 DR1: 00000000e0005000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 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:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:565 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x73/0x90 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4168 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_node_noprof+0x139/0x3b0 mm/slub.c:4271 __alloc_skb+0x10c/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+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+0xf48/0x3940 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+0xd0/0x610 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_write_unlock_bh include/linux/rwlock_api_smp.h:281 [inline] _raw_write_unlock_bh+0x33/0x70 kernel/locking/spinlock.c:366 neigh_parms_alloc+0x41b/0x5c0 net/core/neighbour.c:1738 ipv6_add_dev+0x324/0x1430 net/ipv6/addrconf.c:401 addrconf_notify+0x56e/0xea0 net/ipv6/addrconf.c:3699 notifier_call_chain+0x10b/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+0x115/0x190 net/core/dev.c:2119 register_netdevice+0x12eb/0x19d0 net/core/dev.c:10610 rtnl_newlink_create net/core/rtnetlink.c:3544 [inline] __rtnl_newlink net/core/rtnetlink.c:3762 [inline] rtnl_newlink+0x1648/0x2130 net/core/rtnetlink.c:3775 rtnetlink_rcv_msg+0x87f/0xa00 net/core/rtnetlink.c:6678 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2537 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline] netlink_unicast+0x8c9/0xa60 net/netlink/af_netlink.c:1342 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1886 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x66d/0x6f0 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:52 [inline] do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fdee7190a23 Code: 64 89 02 48 c7 c0 ff ff ff ff eb b7 66 2e 0f 1f 84 00 00 00 00 00 90 80 3d 41 7b 1f 00 00 41 89 ca 74 14 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 75 c3 0f 1f 40 00 55 48 83 ec 30 44 89 4c 24 RSP: 002b:00007ffff67f4678 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fdee7ee4620 RCX: 00007fdee7190a23 RDX: 000000000000003c RSI: 00007fdee7ee4670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffff67f4694 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fdee7ee4670 R15: 0000000000000000 net_ratelimit: 107652 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:92:01:7c:eb:3f:36, 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:1b, 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:92:01:7c:eb:3f:36, 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 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:92:01:7c:eb:3f:36, 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: 128903 callbacks suppressed 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:92:01:7c:eb:3f:36, 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:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:92:01:7c:eb:3f:36, 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: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:92:01:7c:eb:3f:36, vlan:0)