rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=28737, q=1552498 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 9706 (4294970498-4294960792), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 9706 jiffies! g28737 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:25912 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 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: 7273 Comm: kworker/1:17 Not tainted 6.12.0-rc3-syzkaller-00217-g4d939780b705 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_power_efficient gc_worker 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+0x11/0x70 kernel/kcov.c:217 Code: 5b e9 43 cd 5d 00 0f 1f 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 0c 25 c0 d7 03 00 <65> 8b 15 b0 ef 6e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 RSP: 0018:ffffc90000a17740 EFLAGS: 00000046 RAX: ffffffff81c41b5c RBX: 0000000000000000 RCX: ffff88802e69bc00 RDX: 0000000000010100 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffffff81c41b28 R09: 1ffffffff2859300 R10: dffffc0000000000 R11: fffffbfff2859301 R12: dffffc0000000000 R13: ffff88802e69bc00 R14: ffffffff81c41a40 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055558a9dd5c8 CR3: 000000002f244000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: perf_event_task_tick+0x24c/0x390 kernel/events/core.c:4444 sched_tick+0x396/0x610 kernel/sched/core.c:5613 update_process_times+0x202/0x230 kernel/time/timer.c:2524 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x37c/0x500 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x551/0xd50 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1043 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:unwind_next_frame+0x0/0x22d0 arch/x86/kernel/unwind_orc.c:469 Code: cc cc 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 91 4c 89 f7 e8 33 37 bd 00 eb 87 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 81 ec 98 00 00 00 49 RSP: 0018:ffffc90000a17bd8 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffc90000a17be0 RCX: ffffffff917bc000 RDX: dffffc0000000000 RSI: ffffffff81fe62bf RDI: ffffc90000a17be0 RBP: ffffc90000a17c70 R08: 0000000000000000 R09: ffffc90000a17cd0 R10: ffffc90000a17c30 R11: ffffffff8180a0e0 R12: ffff88802e69bc00 R13: ffffffff8180a0e0 R14: ffffc90000a17cc0 R15: 0000000000000000 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 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 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kfree+0x1a0/0x440 mm/slub.c:4727 skb_kfree_head net/core/skbuff.c:1086 [inline] skb_free_head net/core/skbuff.c:1098 [inline] skb_release_data+0x6a0/0x8a0 net/core/skbuff.c:1125 skb_release_all net/core/skbuff.c:1190 [inline] __kfree_skb net/core/skbuff.c:1204 [inline] consume_skb+0x9f/0xf0 net/core/skbuff.c:1436 nft_synproxy_eval_v4+0x3d2/0x610 net/netfilter/nft_synproxy.c:60 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 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_release+0x142/0xa30 kernel/locking/lockdep.c:5838 Code: 8d 98 dc 0a 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 fb 05 00 00 83 3b 00 0f 85 14 05 00 00 4c 89 f0 48 c1 e8 03 <42> 80 3c 38 00 74 08 4c 89 f7 e8 1f 1f 8e 00 48 c7 c0 d0 96 e3 93 RSP: 0018:ffffc9000328f920 EFLAGS: 00000a02 RAX: 1ffffffff1d26fbc RBX: ffff88802e69c6dc RCX: ffffffff81707dc0 RDX: 0000000000000000 RSI: ffffffff8c610180 RDI: ffffffff8c610140 RBP: ffffc9000328fa50 R08: ffffffff901cffaf R09: 1ffffffff2039ff5 R10: dffffc0000000000 R11: fffffbfff2039ff6 R12: 1ffff92000651f30 R13: ffffffff89de725b R14: ffffffff8e937de0 R15: dffffc0000000000 rcu_lock_release include/linux/rcupdate.h:347 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] gc_worker+0xdc8/0x1530 net/netfilter/nf_conntrack_core.c:1609 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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