bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=142745, q=1579 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 3476 (4295039624-4295036148), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 3476 jiffies! g142745 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:28040 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 4976 Comm: klogd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:write_comp_data kernel/kcov.c:246 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x17/0x90 kernel/kcov.c:321 Code: 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d f8 54 74 11 65 8b 15 19 55 74 11 <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 1c 17 00 00 RSP: 0018:ffffc90000007b70 EFLAGS: 00000246 RAX: ffffffff89b44856 RBX: fffffff0a3da8872 RCX: ffff88807ef8dd00 RDX: 0000000000000102 RSI: fffffff0a3da8872 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000000f70 R12: ffff888081003900 R13: 0019999999999998 R14: fffffff0a3da8872 R15: dffffc0000000000 FS: 00007ff9bcb57c80(0000) GS:ffff88812527b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0bfa000000 CR3: 000000007ed6e000 CR4: 00000000003526f0 Call Trace: pie_calculate_probability+0x396/0x7f0 net/sched/sch_pie.c:379 fq_pie_timer+0x27d/0x5a0 net/sched/sch_fq_pie.c:402 call_timer_fn+0x192/0x5e0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2374 [inline] __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386 run_timer_base kernel/time/timer.c:2395 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:preempt_schedule_irq+0x48/0xa0 kernel/sched/core.c:7552 Code: 49 be 00 00 00 00 00 fc ff df eb 09 48 f7 03 10 00 00 00 74 53 bf 01 00 00 00 e8 e3 52 ea f5 e8 8e f9 24 f6 fb bf 01 00 00 00 d3 a2 ff ff 9c 58 fa a9 00 02 00 00 74 05 e8 54 fb 24 f6 bf 01 RSP: 0018:ffffc90003117768 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffffffff8c291100 RDI: 0000000000000001 RBP: 0000000000000000 R08: ffffffff903114f7 R09: 1ffffffff206229e R10: dffffc0000000000 R11: fffffbfff206229f R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:preempt_schedule_thunk+0x0/0x40 arch/x86/entry/thunk.S:12 Code: 87 92 00 48 c7 c0 80 5a c0 8b c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <55> 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 41 53 e8 0a b8 75 0a RSP: 0018:ffffc90003117888 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8c291100 RDI: ffffffff81878ef0 RBP: dffffc0000000000 R08: ffffffff903114f7 R09: 1ffffffff206229e R10: dffffc0000000000 R11: fffffbfff206229f R12: 00000000000000a0 R13: ffffffff89727e49 R14: ffffffff89727e49 R15: 00000000ffffffff __local_bh_enable_ip+0xe1/0x130 kernel/softirq.c:457 local_bh_enable include/linux/bottom_half.h:33 [inline] __alloc_skb+0x1ad/0x7a0 net/core/skbuff.c:699 alloc_skb include/linux/skbuff.h:1386 [inline] alloc_skb_with_frags+0xc6/0x760 net/core/skbuff.c:6769 sock_alloc_send_pskb+0x878/0x990 net/core/sock.c:3010 unix_dgram_sendmsg+0x4da/0x17b0 net/unix/af_unix.c:2136 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] __sys_sendto+0x626/0x6c0 net/socket.c:2252 __do_sys_sendto net/socket.c:2259 [inline] __se_sys_sendto net/socket.c:2255 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2255 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff9bcca7407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffe4ec3b060 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007ff9bcb57c80 RCX: 00007ff9bcca7407 RDX: 00000000000000a0 RSI: 00007ffe4ec3b1a0 RDI: 0000000000000003 RBP: 00007ffe4ec3b5d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffe4ec3b5e8 R13: 00007ffe4ec3b1a0 R14: 0000000000000085 R15: 00007ffe4ec3b1a0 bridge0: received packet on veth1_to_bridge with own address as source address (addr:62:f5:ff:e9:ea:f4, 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:62:f5:ff:e9:ea:f4, 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:62:f5:ff:e9:ea:f4, vlan:0)