INFO: task syz.2.1518:4159 blocked for more than 123 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1518 state:D stack:0 pid:4159 tgid:4159 ppid:296 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6060 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7880 __schedule_loop kernel/sched/core.c:7957 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7972 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+0x368/0x650 kernel/sched/completion.c:127 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148 rcu_barrier+0x45a/0x580 kernel/rcu/tree.c:4657 kvm_mmu_uninit_tdp_mmu+0x1ea/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51 kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6569 kvm_arch_destroy_vm+0x395/0x410 arch/x86/kvm/x86.c:13008 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline] kvm_put_kvm+0xadf/0x12d0 virt/kvm/kvm_main.c:1392 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415 __fput+0x20b/0xa30 fs/file_table.c:447 ____fput+0x20/0x30 fs/file_table.c:475 task_work_run+0x1e8/0x260 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: 0033:0x7f949619de99 RSP: 002b:00007ffe11b5b0b8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007ffe11b5b1a0 RCX: 00007f949619de99 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 0000000000031a3b R08: 0000000000000001 R09: 0000000000000000 R10: 0000001b2e320000 R11: 0000000000000246 R12: 00007ffe11b5b1e0 R13: 00007f9496425fac R14: 0000000000031cfa R15: 00007f9496425fa0 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 9c722142e1cda5d0ace938c6e5c03d461fe7a5ab Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 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+0xe45/0xf90 kernel/hung_task.c:423 kthread+0x2c7/0x360 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: 4174 Comm: syz-executor Not tainted syzkaller #0 9c722142e1cda5d0ace938c6e5c03d461fe7a5ab Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:0xffffffffa0000cec Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 41 ff e3 cc 41 ff e3 cc 41 ff e3 cc <41> ff e3 cc 41 ff e3 cc 41 ff e3 cc 41 ff e3 cc 41 ff e3 cc cc cc RSP: 0018:ffffc9000022ff40 EFLAGS: 00000257 RAX: ffffffff85c0012f RBX: ffffc90000230000 RCX: 0000000000045f00 RDX: ffffc9000f277f01 RSI: ffffffff85c0012f RDI: ffffc90000230000 RBP: ffffc9000022ffd0 R08: ffffc90000230010 R09: ffffc90000230008 R10: 0000000000000000 R11: ffffffff81759ed0 R12: ffff88810e365f00 R13: 0000000000000000 R14: ffffffff81759ed0 R15: ffffc9000022ff48 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6f1ea75110 CR3: 000000010c764000 CR4: 00000000003526b0 DR0: 000000000000000a DR1: 0000000000000006 DR2: 0000000000000003 DR3: 000000000000eda9 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: 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_free_info+0x44/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:249 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:266 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2445 [inline] slab_free mm/slub.c:4714 [inline] kmem_cache_free+0x1bd/0x4f0 mm/slub.c:4825 kfree_skbmem net/core/skbuff.c:-1 [inline] __kfree_skb+0x18f/0x210 net/core/skbuff.c:1200 consume_skb+0x65/0x1a0 net/core/skbuff.c:1431 arp_process+0xe3e/0x1810 net/ipv4/arp.c:942 NF_HOOK+0x17e/0x1e0 include/linux/netfilter.h:317 arp_rcv+0x2f8/0x490 net/ipv4/arp.c:992 __netif_receive_skb_one_core net/core/dev.c:5801 [inline] __netif_receive_skb net/core/dev.c:5914 [inline] netif_receive_skb_internal net/core/dev.c:6000 [inline] netif_receive_skb+0x228/0x7b0 net/core/dev.c:6059 br_netif_receive_skb net/bridge/br_input.c:30 [inline] NF_HOOK include/linux/netfilter.h:317 [inline] br_pass_frame_up+0x126/0x1b0 net/bridge/br_input.c:70 br_handle_frame_finish+0x1178/0x1620 net/bridge/br_input.c:-1 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline] br_handle_frame+0x5a5/0xba0 net/bridge/br_input.c:424 __netif_receive_skb_core+0xfc4/0x3a70 net/core/dev.c:5695 __netif_receive_skb_one_core net/core/dev.c:5799 [inline] __netif_receive_skb net/core/dev.c:5914 [inline] process_backlog+0x40b/0xaf0 net/core/dev.c:6250 __napi_poll+0xd0/0x600 net/core/dev.c:6901 napi_poll net/core/dev.c:6970 [inline] net_rx_action+0x5dc/0xd70 net/core/dev.c:7092 handle_softirqs+0x1aa/0x620 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 __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] __fib6_clean_all+0x39d/0x440 net/ipv6/ip6_fib.c:2288 fib6_clean_all+0x2e/0x50 net/ipv6/ip6_fib.c:2297 rt6_sync_down_dev net/ipv6/route.c:4939 [inline] rt6_disable_ip+0x124/0x810 net/ipv6/route.c:4944 addrconf_ifdown+0x161/0x1970 net/ipv6/addrconf.c:3896 addrconf_notify+0x17a/0xeb0 net/ipv6/addrconf.c:-1 notifier_call_chain+0x106/0x2b0 kernel/notifier.c:93 raw_notifier_call_chain+0x31/0x40 kernel/notifier.c:461 call_netdevice_notifiers_info net/core/dev.c:2074 [inline] call_netdevice_notifiers_extack net/core/dev.c:2112 [inline] call_netdevice_notifiers net/core/dev.c:2126 [inline] unregister_netdevice_many_notify+0xde1/0x1be0 net/core/dev.c:11533 unregister_netdevice_many net/core/dev.c:11595 [inline] unregister_netdevice_queue+0x302/0x350 net/core/dev.c:11469 unregister_netdevice include/linux/netdevice.h:3165 [inline] __tun_detach+0xc98/0x1450 drivers/net/tun.c:685 tun_detach drivers/net/tun.c:701 [inline] tun_chr_close+0x93/0x150 drivers/net/tun.c:3520 __fput+0x20b/0xa30 fs/file_table.c:447 ____fput+0x20/0x30 fs/file_table.c:475 task_work_run+0x1e8/0x260 kernel/task_work.c:246 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xa46/0x2850 kernel/exit.c:955 do_group_exit+0x21f/0x2f0 kernel/exit.c:1098 get_signal+0x134c/0x1490 kernel/signal.c:2933 arch_do_signal_or_restart+0xbc/0x700 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+0x57/0xb0 kernel/entry/common.c:218 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fb43e959017 Code: Unable to access opcode bytes at 0x7fb43e958fed. RSP: 002b:00007ffc696e1840 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: 0000000000000048 RBX: 000055556aea4500 RCX: 00007fb43e959017 RDX: 0000000000000048 RSI: 00007fb43f754670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc696e18a4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fb43f754670 R15: 0000000000000000 net_ratelimit: 87550 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: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:e2:4a:a3:05:fa:76, 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:e2:4a:a3:05:fa:76, vlan:0) net_ratelimit: 107813 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:e2:4a:a3:05:fa:76, 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 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 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:e2:4a:a3:05:fa:76, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)