rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5499/1:b..l rcu: (detected by 0, t=10503 jiffies, g=21345, q=174 ncpus=2) task:dhcpcd state:R running task stack:21456 pid:5499 tgid:5499 ppid:5498 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x0/0xa30 kernel/locking/lockdep.c:5857 Code: 03 38 c1 0f 8c aa f5 ff ff 48 c7 c7 d4 ae 19 90 e8 95 fd 8a 00 e9 99 f5 ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 RSP: 0018:ffffc900030f7958 EFLAGS: 00000293 RAX: ffffffff82115bdf RBX: 0000000000000000 RCX: ffff888030f05a00 RDX: 0000000000000000 RSI: ffffffff82115c37 RDI: ffffffff8e937ae0 RBP: ffffea00015d1080 R08: ffffffff82115bc6 R09: 1ffff11003b48a9d R10: dffffc0000000000 R11: ffffed1003b48a9e R12: ffffea00015d1088 R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000 rcu_lock_release include/linux/rcupdate.h:347 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] page_ext_put+0xa3/0xc0 mm/page_ext.c:550 page_table_check_free include/linux/page_table_check.h:41 [inline] free_pages_prepare mm/page_alloc.c:1128 [inline] free_unref_page+0xd53/0x1010 mm/page_alloc.c:2657 discard_slab mm/slub.c:2688 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3157 put_cpu_partial+0x17c/0x250 mm/slub.c:3232 __slab_free+0x290/0x380 mm/slub.c:4483 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4119 [inline] slab_alloc_node mm/slub.c:4168 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4175 sk_prot_alloc+0x58/0x210 net/core/sock.c:2159 sk_alloc+0x38/0x370 net/core/sock.c:2218 unix_create1+0xb4/0x7a0 unix_create+0x14e/0x200 net/unix/af_unix.c:1094 __sock_create+0x4c0/0xa30 net/socket.c:1558 sock_create net/socket.c:1616 [inline] __sys_socketpair+0x33e/0x720 net/socket.c:1767 __do_sys_socketpair net/socket.c:1816 [inline] __se_sys_socketpair net/socket.c:1813 [inline] __x64_sys_socketpair+0x9b/0xb0 net/socket.c:1813 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f675056bc0a RSP: 002b:00007ffd979fd298 EFLAGS: 00000246 ORIG_RAX: 0000000000000035 RAX: ffffffffffffffda RBX: 000056106901db78 RCX: 00007f675056bc0a RDX: 0000000000000000 RSI: 0000000000080802 RDI: 0000000000000001 RBP: 00007ffd97a1d708 R08: 00007ffd979fd2c0 R09: 000056106901db40 R10: 00007ffd979fd2c0 R11: 0000000000000246 R12: 00007ffd97a1d708 R13: 000056106901db40 R14: 0000000000000000 R15: 000056106901db74 rcu: rcu_preempt kthread starved for 10458 jiffies! g21345 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:24752 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.13.0-rc3-syzkaller-00177-gad5c318086e2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:check_preemption_disabled+0x14/0x120 lib/smp_processor_id.c:13 Code: 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 <48> 89 44 24 08 65 8b 1d 1c 2e 3b 74 65 8b 05 11 2e 3b 74 a9 ff ff RSP: 0018:ffffc90000155ff8 EFLAGS: 00000282 RAX: 2230d03ff7e05100 RBX: 0000000000000001 RCX: ffffffff89941053 RDX: ffff88801cec5a00 RSI: ffffffff8c5faec0 RDI: ffffffff8c5fae80 RBP: 0000000000000001 R08: ffffffff89941079 R09: 1ffffffff2032f86 R10: dffffc0000000000 R11: fffffbfff2032f87 R12: ffff888175847b40 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcee5408000 CR3: 00000000335aa000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:737 trace_net_dev_xmit include/trace/events/net.h:72 [inline] xmit_one net/core/dev.c:3591 [inline] dev_hard_start_xmit+0x392/0x7d0 net/core/dev.c:3606 __dev_queue_xmit+0x1b73/0x3f50 net/core/dev.c:4434 dev_queue_xmit include/linux/netdevice.h:3168 [inline] br_dev_queue_push_xmit+0x726/0x900 net/bridge/br_forward.c:53 NF_HOOK+0x700/0x7c0 include/linux/netfilter.h:314 br_nf_post_routing+0xa20/0xe80 net/bridge/br_netfilter_hooks.c:997 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x2a7/0x460 include/linux/netfilter.h:312 br_forward_finish+0xd8/0x130 net/bridge/br_forward.c:66 br_nf_forward_finish+0xb49/0xfb0 net/bridge/br_netfilter_hooks.c:693 NF_HOOK+0x700/0x7c0 include/linux/netfilter.h:314 br_nf_forward_ip+0x61e/0x7b0 net/bridge/br_netfilter_hooks.c:747 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x2a7/0x460 include/linux/netfilter.h:312 __br_forward+0x489/0x660 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver+0xb3/0x150 net/bridge/br_forward.c:190 br_flood+0x2e4/0x660 net/bridge/br_forward.c:236 br_handle_frame_finish+0x18ba/0x1fe0 net/bridge/br_input.c:215 br_nf_hook_thresh+0x472/0x590 br_nf_pre_routing_finish_ipv6+0xaa0/0xdd0 NF_HOOK include/linux/netfilter.h:314 [inline] br_nf_pre_routing_ipv6+0x379/0x770 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x9fd/0x1530 net/bridge/br_input.c:424 __netif_receive_skb_core+0x14eb/0x4690 net/core/dev.c:5566 __netif_receive_skb_one_core net/core/dev.c:5670 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:5785 process_backlog+0x662/0x15b0 net/core/dev.c:6117 __napi_poll+0xcb/0x490 net/core/dev.c:6883 napi_poll net/core/dev.c:6952 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7074 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 run_ksoftirqd+0xca/0x130 kernel/softirq.c:950 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244