INFO: task kworker/0:8:1291 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:8 state:D stack:0 pid:1291 tgid:1291 ppid:2 flags:0x00004000 Workqueue: events fqdir_free_fn Call Trace: context_switch kernel/sched/core.c:6016 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7870 __schedule_loop kernel/sched/core.c:7951 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7966 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+0x7d1/0x1020 kernel/workqueue.c:3319 worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400 kthread+0x2c6/0x370 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 INFO: task syz.0.584:1944 blocked for more than 123 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.584 state:D stack:0 pid:1944 tgid:1943 ppid:295 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:6016 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7870 __schedule_loop kernel/sched/core.c:7951 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7966 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8023 __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 netdev_run_todo+0x118/0xce0 net/core/dev.c:10887 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0xc5/0x150 drivers/net/tun.c:3520 __fput+0x1fe/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 task_work_run+0x1e8/0x260 kernel/task_work.c:246 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x9ad/0x2720 kernel/exit.c:954 do_group_exit+0x229/0x2f0 kernel/exit.c:1096 get_signal+0x1398/0x14e0 kernel/signal.c:2933 arch_do_signal_or_restart+0xbc/0x760 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: 0033:0x7fb93519c4ab RSP: 002b:00007fb933be0f00 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffffc RBX: 0000000000000004 RCX: 00007fb93519c4ab RDX: 00007fb933be1fd0 RSI: 0000000080085502 RDI: 0000000000000004 RBP: 00007fb933be1fd0 R08: 00007fb935064567 R09: 00007fb933be0fc8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502 R13: 0000000800000000 R14: 0000000000000000 R15: 00007fb935250ede INFO: task syz.3.596:1977 blocked for more than 125 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.596 state:D stack:0 pid:1977 tgid:1977 ppid:294 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6016 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7870 __schedule_loop kernel/sched/core.c:7951 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7966 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8023 __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+0x1fe/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 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: 0033:0x7f7e12f9c819 RSP: 002b:00007fffe51c79c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fffe51c7ab0 RCX: 00007f7e12f9c819 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00000000000164d6 R08: 0000000000000001 R09: 0000000000000000 R10: 0000001b2e120000 R11: 0000000000000246 R12: 00007fffe51c7af0 R13: 00007f7e13215fac R14: 0000000000016524 R15: 00007f7e13215fa0 INFO: task syz.1.601:1991 blocked for more than 127 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.601 state:D stack:0 pid:1991 tgid:1991 ppid:290 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6016 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7870 __schedule_loop kernel/sched/core.c:7951 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7966 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8023 __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 netdev_run_todo+0x118/0xce0 net/core/dev.c:10887 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0xc5/0x150 drivers/net/tun.c:3520 __fput+0x1fe/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 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: 0033:0x7f47f499c819 RSP: 002b:00007ffc4f3ab338 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f47f4c17da0 RCX: 00007f47f499c819 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f47f4c17da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007f47f4c17cb0 R11: 0000000000000246 R12: 0000000000016c29 R13: 00007f47f4c1609c R14: 00000000000169b9 R15: 00007f47f4c16090 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 de3e1d1c5728fabb050931035751e453f935abb5 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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+0x2c6/0x370 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 de3e1d1c5728fabb050931035751e453f935abb5 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0xc/0x70 kernel/kcov.c:216 Code: e9 09 06 1c 04 cc cc cc cc cc cc cc cc cc b8 74 f6 c5 07 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 48 8b 45 08 <65> 48 8b 0d 7c 3f 7d 7e 65 8b 15 7d 3f 7d 7e 81 e2 00 01 ff 00 74 RSP: 0018:ffffc900002302b0 EFLAGS: 00000246 RAX: ffffffff84f95fa1 RBX: 1ffff11020b7e40c RCX: 0000000000000100 RDX: ffff888103660000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900002302b0 R08: ffffc90000230518 R09: 0000000000000017 R10: ffffc900002306b0 R11: fffff520000460da R12: 0000000000000100 R13: dffffc0000000000 R14: ffff888105bf2000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561a6bd1c1f0 CR3: 000000010db68000 CR4: 00000000003526b0 Call Trace: fib6_check_expired include/net/ip6_fib.h:280 [inline] __find_rr_leaf+0x1a1/0x840 net/ipv6/route.c:843 find_rr_leaf net/ipv6/route.c:890 [inline] rt6_select net/ipv6/route.c:934 [inline] fib6_table_lookup+0x2ee/0x9e0 net/ipv6/route.c:2241 ip6_pol_route+0x17a/0x1360 net/ipv6/route.c:2277 ip6_pol_route_input+0x5a/0x80 net/ipv6/route.c:2334 pol_lookup_func include/net/ip6_fib.h:626 [inline] fib6_rule_lookup+0x4ee/0x6d0 net/ipv6/fib6_rules.c:117 ip6_route_input_lookup net/ipv6/route.c:2346 [inline] ip6_route_input+0x62e/0x8f0 net/ipv6/route.c:2642 ip6_rcv_finish_core net/ipv6/ip6_input.c:66 [inline] ip6_rcv_finish+0x15a/0x3e0 net/ipv6/ip6_input.c:77 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] process_backlog+0x44b/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+0x1ad/0x630 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 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+0x2c6/0x370 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 net_ratelimit: 87067 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:32:db:21:a1:24:20, 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: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:32:db:21:a1:24:20, 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:32:db:21:a1:24:20, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)