rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P13265/1:b..l rcu: (detected by 0, t=10503 jiffies, g=149165, q=887 ncpus=2) task:syz-executor state:R running task stack:24096 pid:13265 tgid:13265 ppid:5215 flags:0x20000000 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6997 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+0x658/0xa30 kernel/locking/lockdep.c:5847 Code: 3c 3b 00 74 08 4c 89 f7 e8 f5 1f 8e 00 f6 84 24 91 00 00 00 02 75 77 41 f7 c5 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc90003c17560 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000782ebe RCX: ffffc90003c17503 RDX: 0000000000000001 RSI: ffffffff8c0adbc0 RDI: ffffffff8c6100a0 RBP: ffffc90003c17690 R08: ffffffff901ce56f R09: 1ffffffff2039cad R10: dffffc0000000000 R11: fffffbfff2039cae R12: 1ffff92000782eb8 R13: 0000000000000246 R14: ffffc90003c175f0 R15: dffffc0000000000 rcu_lock_release include/linux/rcupdate.h:347 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] pte_unmap include/linux/pgtable.h:115 [inline] insert_page mm/memory.c:2080 [inline] vm_insert_page+0x59a/0x710 mm/memory.c:2229 kcov_mmap+0xd7/0x140 kernel/kcov.c:506 call_mmap include/linux/fs.h:2172 [inline] mmap_region+0x1add/0x2990 mm/mmap.c:1440 do_mmap+0x8f0/0x1000 mm/mmap.c:496 vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:588 ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:542 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7f66579 RSP: 002b:00000000fff052b0 EFLAGS: 00000206 ORIG_RAX: 00000000000000c0 RAX: ffffffffffffffda RBX: 00000000f6aef000 RCX: 0000000000200000 RDX: 0000000000000003 RSI: 0000000000000011 RDI: 00000000000000d8 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 6742 jiffies! g149165 f0x0 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:24304 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 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: 937 Comm: kworker/1:2 Not tainted 6.11.0-syzkaller-10622-gaa486552a110 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:19 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:87 [inline] RIP: 0010:lockdep_hardirqs_on_prepare+0xee/0x780 kernel/locking/lockdep.c:4384 Code: 03 0f b6 04 10 84 c0 0f 85 33 05 00 00 83 3d 38 1f cc 18 00 0f 85 a8 00 00 00 4c 8d 74 24 40 4c 89 f3 48 c1 eb 03 80 3c 13 00 <74> 12 4c 89 f7 e8 48 89 8e 00 48 ba 00 00 00 00 00 fc ff df 48 c7 RSP: 0018:ffffc90000a17ae0 EFLAGS: 00000046 RAX: 0000000000000004 RBX: 1ffff92000142f64 RCX: ffffffff9a3bf903 RDX: dffffc0000000000 RSI: ffffffff8c610080 RDI: ffffffff8c610040 RBP: ffffc90000a17b88 R08: ffffffff901ce56f R09: 1ffffffff2039cad R10: dffffc0000000000 R11: fffffbfff2039cae R12: dffffc0000000000 R13: 1ffff92000142f7c R14: ffffc90000a17b20 R15: 1ffff92000142f60 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe3e044038 CR3: 000000005f246000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000097 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: trace_hardirqs_on+0x28/0x40 kernel/trace/trace_preemptirq.c:61 __local_bh_enable_ip+0x168/0x200 kernel/softirq.c:387 local_bh_enable include/linux/bottom_half.h:33 [inline] ipt_do_table+0x1552/0x1860 net/ipv4/netfilter/ip_tables.c:357 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook+0x2c4/0x450 include/linux/netfilter.h:269 __ip_local_out+0x3d9/0x4e0 net/ipv4/ip_output.c:119 ip_local_out+0x26/0x70 net/ipv4/ip_output.c:128 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:5662 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5775 process_backlog+0x662/0x15b0 net/core/dev.c:6107 __napi_poll+0xcb/0x490 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6962 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 neigh_periodic_work+0xb35/0xd50 net/core/neighbour.c:1019 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