INFO: task kworker/1:3:312 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:3 state:D stack:0 pid:312 tgid:312 ppid:2 flags:0x00004000 Workqueue: events fqdir_free_fn Call Trace: context_switch kernel/sched/core.c:6027 [inline] __schedule+0x14ce/0x2100 kernel/sched/core.c:7894 __schedule_loop kernel/sched/core.c:7975 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7990 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:3261 [inline] process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3342 worker_thread+0xc51/0x1370 kernel/workqueue.c:3423 kthread+0x2c9/0x370 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 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 471281939cd7bfdfff4c6b6074d5d68627c837ba Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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+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: 33 Comm: rcuop/1 Not tainted syzkaller #0 471281939cd7bfdfff4c6b6074d5d68627c837ba Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:__kasan_init_slab_obj+0x14/0x20 mm/kasan/common.c:210 Code: cc 0f 1f 44 00 00 b8 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 48 89 e5 53 48 89 f3 e8 2f 2b 00 00 48 89 d8 <5b> 5d e9 55 b4 ca 03 cc 0f 1f 40 00 b8 00 00 00 00 90 90 90 90 90 RSP: 0018:ffffc9000022fd58 EFLAGS: 00000246 RAX: ffff888193166780 RBX: ffff888193166780 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8881931667b0 RBP: ffffc9000022fd60 R08: dffffc0000000000 R09: 0000000000000000 R10: ffff8881931667a0 R11: fffff94000c98b37 R12: 0000000000000035 R13: ffff888193166a00 R14: ffffea00064c5980 R15: 000000000000001c FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000563144ed1af8 CR3: 000000010c70a000 CR4: 00000000003526b0 Call Trace: kasan_init_slab_obj include/linux/kasan.h:178 [inline] setup_object+0x14/0xf0 mm/slub.c:2495 shuffle_freelist mm/slub.c:2622 [inline] allocate_slab+0x258/0x420 mm/slub.c:2716 new_slab mm/slub.c:2741 [inline] ___slab_alloc+0x5a2/0x8d0 mm/slub.c:3934 __slab_alloc mm/slub.c:4025 [inline] __slab_alloc_node mm/slub.c:4078 [inline] slab_alloc_node mm/slub.c:4239 [inline] __kmalloc_cache_noprof+0x2cd/0x470 mm/slub.c:4421 kmalloc_noprof include/linux/slab.h:881 [inline] kzalloc_noprof include/linux/slab.h:1017 [inline] ref_tracker_alloc+0x184/0x590 lib/ref_tracker.c:203 __netdev_tracker_alloc include/linux/netdevice.h:4142 [inline] netdev_hold include/linux/netdevice.h:4171 [inline] dst_init+0xcf/0x440 net/core/dst.c:52 dst_alloc+0x163/0x250 net/core/dst.c:94 rt_dst_alloc net/ipv4/route.c:1647 [inline] ip_route_input_slow net/ipv4/route.c:2385 [inline] ip_route_input_rcu+0x1a0e/0x2700 net/ipv4/route.c:2499 ip_route_input_noref+0xd4/0x150 net/ipv4/route.c:2510 arp_process+0x908/0x1790 net/ipv4/arp.c:841 NF_HOOK+0x181/0x1e0 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+0x22a/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+0x120c/0x17a0 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+0xfae/0x3ab0 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+0x3e5/0xad0 net/core/dev.c:6250 __napi_poll+0xd0/0x610 net/core/dev.c:6901 napi_poll net/core/dev.c:6970 [inline] net_rx_action+0x5ea/0xd80 net/core/dev.c:7092 handle_softirqs+0x1aa/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+0x2c9/0x370 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: 81974 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:00:00:00:00:14:bb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:00:00:00:00:14:bb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:00:00:00:00:14:bb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:00:00:00:00:14:bb, 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:00:00:00:00:14:bb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:00:00:00:00:14:bb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:00:00:00:00:14:bb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:00:00:00:00:14:bb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:00:00:00:00:14:bb, vlan:0)