rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5158/1:b..l rcu: (detected by 1, t=10502 jiffies, g=10721, q=14046 ncpus=2) task:udevd state:R running task stack:24944 pid:5158 ppid:1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009 irqentry_exit+0x67/0x70 kernel/entry/common.c:438 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:unwind_done arch/x86/include/asm/unwind.h:50 [inline] RIP: 0010:unwind_get_return_address+0x1c/0xc0 arch/x86/kernel/unwind_orc.c:366 Code: e9 3c ff ff ff e8 14 2b 34 09 0f 1f 40 00 f3 0f 1e fa 55 41 57 41 56 53 48 89 fb 49 be 00 00 00 00 00 fc ff df e8 d4 ed 4a 00 <48> 89 d8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 6e 8b 2b 31 ff 89 ee RSP: 0018:ffffc90003487700 EFLAGS: 00000293 RAX: ffffffff813aa1bc RBX: ffffc90003487728 RCX: ffff88807dc5bc00 RDX: 0000000000000000 RSI: 0000000080000000 RDI: ffffc90003487728 RBP: ffffc900034877b0 R08: ffff88807dc5bc00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000000 R12: ffffffff81dc7eac R13: 1ffff92000690f10 R14: dffffc0000000000 R15: ffffc90003487728 arch_stack_walk+0x11d/0x190 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf7/0x1f0 mm/page_owner.c:128 __reset_page_owner+0x4e/0x190 mm/page_owner.c:149 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2127 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667 put_cpu_partial+0x17c/0x250 mm/slub.c:2743 __slab_free+0x31d/0x410 mm/slub.c:3700 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3519 getname_flags+0xbb/0x500 fs/namei.c:140 vfs_fstatat+0x111/0x1b0 fs/stat.c:298 __do_sys_newfstatat fs/stat.c:463 [inline] __se_sys_newfstatat fs/stat.c:457 [inline] __x64_sys_newfstatat+0x117/0x190 fs/stat.c:457 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fee4e911b0a RSP: 002b:00007ffeaa94e978 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 00005558f3627408 RCX: 00007fee4e911b0a RDX: 00007ffeaa94e980 RSI: 00005558f3615ef3 RDI: 00000000ffffff9c RBP: 00005558ffcc9148 R08: 00063489548db180 R09: 0000000000745a24 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffeaa94e980 R14: 0000000000000000 R15: 00063489548db180 rcu: rcu_preempt kthread starved for 464 jiffies! g10721 f0x0 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:26760 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 schedule_timeout+0x160/0x280 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6289 Comm: syz.1.121 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:__asan_memset+0x5/0x40 mm/kasan/shadow.c:83 Code: 0f 1f 44 00 00 f3 0f 1e fa 89 f6 48 8b 0c 24 ba 01 00 00 00 e9 bc ea ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 55 <41> 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 RSP: 0018:ffffc90000006488 EFLAGS: 00000246 RAX: ffffc900192cff20 RBX: ffffc900000065a0 RCX: ffff88802a1b3c00 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc900000065b8 RBP: ffffc900000065b8 R08: ffff88802a1b3c00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000100 R12: ffffc90000006568 R13: dffffc0000000000 R14: ffffffff8a6e8505 R15: ffffffff8ecdd02c FS: 00007f72d9b556c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd5ce53b0c CR3: 0000000025404000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: unwind_next_frame+0x1648/0x2970 arch/x86/kernel/unwind_orc.c:592 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x280 mm/slub.c:3852 skb_ext_del include/linux/skbuff.h:4786 [inline] nf_bridge_info_free net/bridge/br_netfilter_hooks.c:152 [inline] br_nf_dev_queue_xmit+0x48f/0x1b90 net/bridge/br_netfilter_hooks.c:-1 NF_HOOK+0x613/0x6a0 include/linux/netfilter.h:304 br_nf_post_routing+0xb41/0xfb0 net/bridge/br_netfilter_hooks.c:977 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline] nf_hook_slow+0xbd/0x200 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:259 [inline] NF_HOOK+0x213/0x3d0 include/linux/netfilter.h:302 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66 br_nf_hook_thresh net/bridge/br_netfilter_hooks.c:-1 [inline] br_nf_forward_finish+0xa33/0xe50 net/bridge/br_netfilter_hooks.c:684 NF_HOOK+0x613/0x6a0 include/linux/netfilter.h:304 br_nf_forward_ip+0xcc1/0x1110 net/bridge/br_netfilter_hooks.c:754 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline] nf_hook_slow+0xbd/0x200 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:259 [inline] NF_HOOK+0x213/0x3d0 include/linux/netfilter.h:302 __br_forward+0x41f/0x600 net/bridge/br_forward.c:115 br_handle_frame_finish+0x144f/0x1920 net/bridge/br_input.c:215 br_nf_hook_thresh+0x3b6/0x480 net/bridge/br_netfilter_hooks.c:1184 br_nf_pre_routing_finish_ipv6+0x9e3/0xd90 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:304 [inline] br_nf_pre_routing_ipv6+0x34d/0x680 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x96b/0x1480 net/bridge/br_input.c:424 __netif_receive_skb_core+0xf6b/0x3ac0 net/core/dev.c:5502 __netif_receive_skb_one_core net/core/dev.c:5606 [inline] __netif_receive_skb+0x74/0x290 net/core/dev.c:5722 process_backlog+0x380/0x6e0 net/core/dev.c:6050 __napi_poll+0xc0/0x460 net/core/dev.c:6612 napi_poll net/core/dev.c:6679 [inline] net_rx_action+0x5ea/0xbf0 net/core/dev.c:6815 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__sanitizer_cov_trace_pc+0x49/0x60 kernel/kcov.c:222 Code: 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 <8b> 89 fc 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 c3 0f 1f RSP: 0018:ffffc900192cf4a8 EFLAGS: 00000246 RAX: ffffffff8863d995 RBX: 0000000000000000 RCX: ffff88802a1b3c00 RDX: ffffc9000dd8b000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: 0000000000000001 R08: ffffffff90da850f R09: 1ffffffff21b50a1 R10: dffffc0000000000 R11: fffffbfff21b50a2 R12: 0000000000000000 R13: ffff88805c39d898 R14: ffff88805c39d801 R15: 0000000000000001 skb_unref include/linux/skbuff.h:1213 [inline] consume_skb+0xc5/0x110 net/core/skbuff.c:1279 netlink_broadcast_filtered+0x109a/0x1110 net/netlink/af_netlink.c:1546 netlink_broadcast net/netlink/af_netlink.c:1560 [inline] nlmsg_multicast include/net/netlink.h:1090 [inline] nlmsg_notify+0xf0/0x1a0 net/netlink/af_netlink.c:2588 __devinet_sysctl_register+0x3e5/0x450 net/ipv4/devinet.c:2639 devinet_init_net+0x32b/0x5c0 net/ipv4/devinet.c:2756 ops_init+0x397/0x640 net/core/net_namespace.c:139 setup_net+0x3a5/0xa00 net/core/net_namespace.c:343 copy_net_ns+0x36d/0x5e0 net/core/net_namespace.c:520 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 copy_namespaces+0x430/0x4a0 kernel/nsproxy.c:179 copy_process+0x1700/0x3d70 kernel/fork.c:2509 kernel_clone+0x21b/0x840 kernel/fork.c:2914 __do_sys_clone kernel/fork.c:3057 [inline] __se_sys_clone kernel/fork.c:3041 [inline] __x64_sys_clone+0x18c/0x1e0 kernel/fork.c:3041 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f72d8d8f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f72d9b54fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f72d8fe5fa0 RCX: 00007f72d8d8f749 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000400c0000 RBP: 00007f72d8e13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f72d8fe6038 R14: 00007f72d8fe5fa0 R15: 00007fffcf438d68 net_ratelimit: 1353 callbacks suppressed 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 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:ff:0e:11:35:93, 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 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 bridge_slave_0 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:aa:aa:aa:aa:aa:0c, vlan:0) net_ratelimit: 1521 callbacks suppressed 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 bridge_slave_0 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: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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)