INFO: task syz.1.7060:21755 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.7060 state:D stack:0 pid:21755 tgid:21755 ppid:21263 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 request_wait_answer fs/fuse/dev.c:476 [inline] __fuse_request_send fs/fuse/dev.c:491 [inline] __fuse_simple_request+0xdb1/0x1980 fs/fuse/dev.c:586 fuse_simple_request fs/fuse/fuse_i.h:1248 [inline] fuse_flush+0x909/0x1d50 fs/fuse/file.c:584 filp_flush fs/open.c:1550 [inline] filp_close+0xc0/0x160 fs/open.c:1563 __range_close fs/file.c:710 [inline] __close_range+0x50e/0x6c0 fs/file.c:767 __do_sys_close_range fs/open.c:1616 [inline] __se_sys_close_range fs/open.c:1613 [inline] __x64_sys_close_range+0x7e/0x90 fs/open.c:1613 x64_sys_call+0x1686/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:437 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: 0033:0x7f50af18f6c9 RSP: 002b:00007fff5eb669c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 000000000007487d RCX: 00007f50af18f6c9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f50af3e7da0 R08: 0000000000000001 R09: 0000000a5eb66cbf R10: 0000001b2c520000 R11: 0000000000000246 R12: 00007f50af3e5fac R13: 00007f50af3e5fa0 R14: ffffffffffffffff R15: 00007fff5eb66ae0 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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: 9 Comm: kworker/0:0 Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x15/0x70 kernel/kcov.c:217 Code: cc cc cc cc cc b8 57 83 4b fe 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 0c 25 00 eb 04 00 <65> 8b 15 3c ec 7e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 RSP: 0018:ffffc90000007750 EFLAGS: 00000297 RAX: ffffffff85012f2a RBX: 0000000000000002 RCX: ffff888102650000 RDX: ffff888102650000 RSI: 0000000000000002 RDI: 000000000000ffff RBP: ffffc90000007750 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000000ea0 R12: dffffc0000000000 R13: ffff88813c3fc800 R14: ffff888176bd8140 R15: 1ffff92000000efc FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556fad9ebff0 CR3: 000000010bf1c000 CR4: 00000000003526b0 DR0: 0000000000000011 DR1: 0000000000000001 DR2: 0000000000000003 DR3: 0000000000000009 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: skb_mac_header include/linux/skbuff.h:3056 [inline] eth_hdr include/linux/if_ether.h:24 [inline] br_handle_frame_finish+0x43a/0x1720 net/bridge/br_input.c:146 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+0xf4b/0x3940 net/core/dev.c:5663 __netif_receive_skb_one_core net/core/dev.c:5767 [inline] __netif_receive_skb net/core/dev.c:5882 [inline] process_backlog+0x3e5/0xae0 net/core/dev.c:6218 __napi_poll+0xd3/0x610 net/core/dev.c:6869 napi_poll net/core/dev.c:6938 [inline] net_rx_action+0x584/0xce0 net/core/dev.c:7060 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_periodic_work+0xa73/0xbc0 net/core/neighbour.c:1019 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3319 worker_thread+0xc58/0x1250 kernel/workqueue.c:3400 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 net_ratelimit: 147627 callbacks suppressed 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 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:aa:aa:aa:aa:aa:0c, 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 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:6e:b1:a4:ba:aa:e3, 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 bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, 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:6e:b1:a4:ba:aa:e3, vlan:0)