INFO: task syz.1.543:2045 blocked for more than 123 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.543 state:D stack:0 pid:2045 tgid:2045 ppid:292 flags:0x00004004 Call Trace: 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:12970 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: 0033:0x7f9d4ab9c799 RSP: 002b:00007ffd6ffc9ff8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f9d4ae17da0 RCX: 00007f9d4ab9c799 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f9d4ae17da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00000000003ffbb4 R11: 0000000000000246 R12: 0000000000017294 R13: 00007f9d4ae15fac R14: 000000000001706b R15: 00007f9d4ae15fa0 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 8f04cd43f1f8ed7fc1b7b2f4f03dd2f28c995d7b Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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+0xdad/0xf00 kernel/hung_task.c:423 kthread+0x2c9/0x370 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: 2152 Comm: syz-executor Not tainted syzkaller #0 8f04cd43f1f8ed7fc1b7b2f4f03dd2f28c995d7b Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:stack_trace_consume_entry+0xf8/0x2a0 kernel/stacktrace.c:93 Code: 89 e2 4c 89 ff 48 8b 75 c0 4c 8b 37 45 8d 7a 01 0f b6 04 13 84 c0 0f 85 4a 01 00 00 45 89 38 4f 8d 3c d6 4c 89 f8 48 c1 e8 03 <80> 3c 10 00 74 1e 4c 89 ff 49 89 d6 4d 89 c4 4c 89 cb e8 a1 b3 69 RSP: 0018:ffffc90000006f50 EFLAGS: 00000a06 RAX: 1ffff92000000e2b RBX: 1ffff92000000e0e RCX: 0000000000006f00 RDX: dffffc0000000000 RSI: ffffffff847e7ec0 RDI: ffffc90000007060 RBP: ffffc90000006f98 R08: ffffc90000007070 R09: ffffc90000007068 R10: 000000000000000f R11: ffffffff8175cab0 R12: ffffc9000000706c R13: 1ffff92000000e0d R14: ffffc900000070e0 R15: ffffc90000007158 FS: 000055557f5d5500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f87325f84c0 CR3: 0000000145ee2000 CR4: 00000000003526b0 Call Trace: arch_stack_walk+0x12c/0x170 arch/x86/kernel/stacktrace.c:27 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+0x4a/0x60 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:4821 kfree_skbmem net/core/skbuff.c:-1 [inline] __kfree_skb+0x18f/0x210 net/core/skbuff.c:1203 sk_skb_reason_drop+0xd8/0x310 net/core/skbuff.c:1240 kfree_skb_reason include/linux/skbuff.h:1271 [inline] kfree_skb include/linux/skbuff.h:1280 [inline] ip6_mc_input+0x516/0x6c0 net/ipv6/ip6_input.c:587 dst_input include/net/dst.h:469 [inline] ip6_rcv_finish+0x363/0x3e0 net/ipv6/ip6_input.c:79 NF_HOOK include/linux/netfilter.h:317 [inline] ipv6_rcv+0xf1/0x240 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core net/core/dev.c:5776 [inline] __netif_receive_skb net/core/dev.c:5889 [inline] netif_receive_skb_internal net/core/dev.c:5975 [inline] netif_receive_skb+0x147/0x7b0 net/core/dev.c:6034 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+0x1317/0x1760 net/bridge/br_input.c:221 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:5670 __netif_receive_skb_one_core net/core/dev.c:5774 [inline] __netif_receive_skb net/core/dev.c:5889 [inline] process_backlog+0x3e5/0xad0 net/core/dev.c:6225 __napi_poll+0xd0/0x610 net/core/dev.c:6876 napi_poll net/core/dev.c:6945 [inline] net_rx_action+0x5ea/0xd80 net/core/dev.c:7067 handle_softirqs+0x1aa/0x630 kernel/softirq.c:621 __do_softirq kernel/softirq.c:659 [inline] invoke_softirq kernel/softirq.c:476 [inline] __irq_exit_rcu+0x47/0xb0 kernel/softirq.c:708 irq_exit_rcu+0xd/0x30 kernel/softirq.c:720 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x82/0x90 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2076 [inline] RIP: 0010:vprintk_emit+0x547/0x650 kernel/printk/printk.c:2461 Code: 81 e6 00 02 00 00 31 ff e8 b6 c5 1e 00 48 81 e3 00 02 00 00 75 07 e8 c8 c0 1e 00 eb 06 e8 c1 c0 1e 00 fb c6 05 d9 3f 52 07 00 31 fd ff ff e8 af c0 1e 00 e9 94 fe ff ff 41 ff ce bf 58 89 41 RSP: 0018:ffffc9000b8cf500 EFLAGS: 00000293 RAX: ffffffff8168db5f RBX: 0000000000000200 RCX: ffff888116ad8000 RDX: 0000000000000000 RSI: 0000000000000200 RDI: 0000000000000000 RBP: ffffc9000b8cf5c8 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52001719e90 R12: 1ffff92001719ea4 R13: 0000000000000009 R14: 0000000000000000 R15: dffffc0000000000 vprintk_default+0x2a/0x40 kernel/printk/printk.c:2477 vprintk+0x93/0xa0 kernel/printk/printk_safe.c:75 _printk+0xde/0x140 kernel/printk/printk.c:2487 __show_mem+0xcb/0x2940 mm/show_mem.c:413 warn_alloc_show_mem+0x147/0x260 mm/page_alloc.c:4002 warn_alloc+0x1f3/0x2c0 mm/page_alloc.c:4028 __vmalloc_area_node mm/vmalloc.c:3666 [inline] __vmalloc_node_range_noprof+0x6aa/0x1480 mm/vmalloc.c:3866 vmalloc_user_noprof+0x77/0x90 mm/vmalloc.c:4026 kcov_ioctl+0x5d/0x5a0 kernel/kcov.c:716 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0x135/0x1b0 fs/ioctl.c:893 __x64_sys_ioctl+0x7f/0xa0 fs/ioctl.c:893 x64_sys_call+0x1878/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:17 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f3209f9c42b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007fffcb87f4f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000080000 RCX: 00007f3209f9c42b RDX: 0000000000080000 RSI: ffffffff80086301 RDI: 00000000000000d9 RBP: 00007f320a216128 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 00007fffcb87f7a8 R15: 0000000000000000 net_ratelimit: 96607 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) net_ratelimit: 125420 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:32:c7:a8:00:c8:c9, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)