rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1/1:b..l rcu: (detected by 0, t=10502 jiffies, g=35225, q=1530414 ncpus=2) task:init state:R running task stack:17680 pid:1 tgid:1 ppid:0 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x18af/0x4bd0 kernel/sched/core.c:6690 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7012 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:filter_irq_stacks+0x2e/0xa0 kernel/stacktrace.c:396 Code: 55 41 57 41 56 41 55 41 54 53 85 f6 74 72 49 89 fe 41 89 f4 45 31 ff 48 c7 c5 30 02 e0 8b 49 c7 c5 10 5a d0 8b 48 89 fb eb 0c <49> ff c7 48 83 c3 08 4d 39 fc 74 4f 48 89 d8 48 c1 e8 03 48 b9 00 RSP: 0018:ffffc90000067748 EFLAGS: 00000287 RAX: ffffffff81f345eb RBX: ffffc90000067828 RCX: dffffc0000000000 RDX: 0000000000002800 RSI: 000000000000000b RDI: ffffc90000067820 RBP: ffffffff8be00230 R08: ffffffff901cfeaf R09: 1ffffffff2039fd5 R10: dffffc0000000000 R11: fffffbfff2039fd6 R12: 000000000000000b R13: ffffffff8bd05a10 R14: ffffc90000067820 R15: 0000000000000001 stack_depot_save_flags+0x29/0x830 lib/stackdepot.c:609 save_stack+0x109/0x1f0 mm/page_owner.c:157 __reset_page_owner+0x76/0x430 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638 __slab_free+0x31b/0x3d0 mm/slub.c:4490 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_kmalloc+0x23/0xb0 mm/kasan/common.c:385 kasan_kmalloc include/linux/kasan.h:257 [inline] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4295 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] task_numa_work+0x85e/0x1510 kernel/sched/fair.c:3402 task_work_run+0x24f/0x310 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f631525d476 RSP: 002b:00007ffc243cac18 EFLAGS: 00000246 ORIG_RAX: 000000000000003d RAX: 0000000000001ce0 RBX: 00007f631541e13c RCX: 00007f631525d476 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00000000ffffffff RBP: 00007f6315423528 R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f63154234a0 R13: 00007ffc243cac38 R14: 0000557b3c393169 R15: 00007f631545aa80 rcu: rcu_preempt kthread starved for 4858 jiffies! g35225 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 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:25008 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x18af/0x4bd0 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.12.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:arch_stack_walk+0x12e/0x150 Code: f7 48 89 c6 4d 89 eb 41 ff d3 66 90 84 c0 74 11 48 89 df e8 e4 9d 09 00 83 bd 70 ff ff ff 00 75 d0 65 48 8b 04 25 28 00 00 00 <48> 3b 45 d0 75 13 48 83 c4 68 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc RSP: 0018:ffffc900001e6540 EFLAGS: 00000246 RAX: b3e3d2b190f7f800 RBX: ffffc900001e6540 RCX: 0000000000000101 RDX: ffffffff909e02f8 RSI: ffffffff909e0280 RDI: 0000000000000001 RBP: ffffc900001e65d0 R08: 000000000000001b R09: ffffc900001e6630 R10: ffffc900001e6590 R11: ffffffff8180a0c0 R12: ffff88801d2e8000 R13: ffffffff8180a0c0 R14: ffffc900001e6620 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c36e0e1 CR3: 000000003200e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4141 dst_alloc+0x12b/0x190 net/core/dst.c:89 rt_dst_alloc net/ipv4/route.c:1612 [inline] __mkroute_output net/ipv4/route.c:2573 [inline] ip_route_output_key_hash_rcu+0x13cc/0x2390 net/ipv4/route.c:2795 ip_route_output_key_hash+0x193/0x2b0 net/ipv4/route.c:2624 __ip_route_output_key include/net/route.h:141 [inline] ip_route_output_flow+0x29/0x140 net/ipv4/route.c:2852 ip_route_output_key include/net/route.h:151 [inline] ip_route_me_harder+0x80d/0x1300 net/ipv4/netfilter.c:53 synproxy_send_tcp+0x356/0x6c0 net/netfilter/nf_synproxy_core.c:431 synproxy_send_client_synack+0x8b8/0xf30 net/netfilter/nf_synproxy_core.c:484 nft_synproxy_eval_v4+0x3ca/0x610 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161 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+0x29e/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5666 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5779 process_backlog+0x662/0x15b0 net/core/dev.c:6111 __napi_poll+0xcb/0x490 net/core/dev.c:6775 napi_poll net/core/dev.c:6844 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6966 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927 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