rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6541/1:b..l rcu: (detected by 0, t=10503 jiffies, g=19601, q=814 ncpus=2) task:syz.0.331 state:R running task stack:26192 pid:6541 tgid:6540 ppid:5243 flags:0x20004004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6854 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6878 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] zap_pte_range mm/memory.c:1691 [inline] zap_pmd_range mm/memory.c:1739 [inline] zap_pud_range mm/memory.c:1768 [inline] zap_p4d_range mm/memory.c:1789 [inline] unmap_page_range+0x36b1/0x40e0 mm/memory.c:1810 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900 exit_mmap+0x275/0xc40 mm/mmap.c:1864 __mmput+0x115/0x390 kernel/fork.c:1347 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x28e0 kernel/exit.c:926 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 get_signal+0x176f/0x1810 kernel/signal.c:2936 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [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+0xc9/0x370 kernel/entry/common.c:218 __do_fast_syscall_32+0xc4/0x110 arch/x86/entry/common.c:389 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7f70579 RSP: 002b:00000000f56f4494 EFLAGS: 00000206 ORIG_RAX: 0000000000000036 RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 0000000080085502 RDX: 00000000f56f5520 RSI: 00000000f73fbff4 RDI: 00000000f56f4544 RBP: 00000000f73fbff4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10471 jiffies! g19601 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:23728 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: 5227 Comm: kworker/1:3 Not tainted 6.11.0-syzkaller-10547-g684a64bf32b6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: events_power_efficient wg_ratelimiter_gc_entries RIP: 0010:rdtsc_ordered arch/x86/include/asm/msr.h:217 [inline] RIP: 0010:read_tsc+0xc/0x20 arch/x86/kernel/tsc.c:1132 Code: be 03 e9 a6 fd ff ff e8 c2 a4 8e 0a 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa e8 97 15 5f 00 0f 01 f9 <66> 90 48 c1 e2 20 48 09 d0 c3 cc cc cc cc 66 0f 1f 44 00 00 90 90 RSP: 0018:ffffc90000a170b8 EFLAGS: 00000006 RAX: 000000007f691cb2 RBX: ffffffff8e76c4e0 RCX: 0000000000000001 RDX: 000000000000008a RSI: 0000000000000000 RDI: ffffffff8e76c4e0 RBP: dffffc0000000000 R08: ffffffff81825700 R09: 1ffffffff2039cad R10: dffffc0000000000 R11: ffffffff81359fa0 R12: 0000000000000000 R13: ffffffff8e958738 R14: ffffffff8e958748 R15: 000000000000cb20 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000f524ea02 CR3: 000000002e500000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tk_clock_read kernel/time/timekeeping.c:195 [inline] timekeeping_debug_get_ns kernel/time/timekeeping.c:257 [inline] timekeeping_get_ns+0xcf/0x420 kernel/time/timekeeping.c:401 ktime_get+0x89/0xb0 kernel/time/timekeeping.c:850 __hrtimer_start_range_ns kernel/time/hrtimer.c:1246 [inline] hrtimer_start_range_ns+0x35f/0xca0 kernel/time/hrtimer.c:1302 hrtimer_start include/linux/hrtimer.h:275 [inline] dummy_timer+0x4421/0x45a0 drivers/usb/gadget/udc/dummy_hcd.c:1998 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x59b/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:seqcount_lockdep_reader_access+0x1e0/0x220 include/linux/seqlock.h:75 Code: 00 4d 85 ed 75 16 e8 1f 5f 12 00 eb 15 e8 18 5f 12 00 e8 43 ef 41 0a 4d 85 ed 74 ea e8 09 5f 12 00 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00 RSP: 0018:ffffc90000a17840 EFLAGS: 00000246 RAX: ffffffff81825637 RBX: 0000000000000000 RCX: ffff88801c343c00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000a178f8 R08: ffffffff8182560d R09: 1ffffffff284d113 R10: dffffc0000000000 R11: fffffbfff284d114 R12: dffffc0000000000 R13: 0000000000000200 R14: 0000000000000046 R15: 1ffff92000142f08 ktime_get_with_offset+0x83/0x150 kernel/time/timekeeping.c:891 ktime_get_real include/linux/timekeeping.h:82 [inline] netif_rx_internal+0x459/0x630 net/core/dev.c:5168 __netif_rx+0x78/0xc0 net/core/dev.c:5211 loopback_xmit+0x454/0x6b0 drivers/net/loopback.c:89 __netdev_start_xmit include/linux/netdevice.h:4916 [inline] netdev_start_xmit include/linux/netdevice.h:4925 [inline] xmit_one net/core/dev.c:3588 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3604 __dev_queue_xmit+0x1b58/0x3e80 net/core/dev.c:4424 dev_queue_xmit include/linux/netdevice.h:3094 [inline] neigh_hh_output include/net/neighbour.h:526 [inline] neigh_output include/net/neighbour.h:540 [inline] ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:236 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 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:__might_resched+0xa/0x780 kernel/sched/core.c:8586 Code: 89 df e8 29 ba 99 00 e9 63 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 48 83 e4 e0 48 81 ec e0 00 00 00 41 89 d4 41 RSP: 0018:ffffc90002d1fb50 EFLAGS: 00000246 RAX: ffffffff866ea13a RBX: 0000000000001a60 RCX: ffff88801c343c00 RDX: 0000000000000000 RSI: 000000000000004e RDI: ffffffff8c984040 RBP: ffffc90002d1fb58 R08: ffffffff8f446143 R09: 1ffffffff1e88c28 R10: dffffc0000000000 R11: fffffbfff1e88c29 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000003d659031da R15: ffffffff8f446260 wg_ratelimiter_gc_entries+0x3cd/0x470 drivers/net/wireguard/ratelimiter.c:78 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