rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=7644/1/0x4000000000000000 softirq=11947/11949 fqs=1 rcu: (detected by 1, t=10502 jiffies, g=8733, q=628 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8 Comm: kworker/0:0 Not tainted 6.14.0-rc2-syzkaller-00281-g496659003dac #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events_power_efficient wg_ratelimiter_gc_entries RIP: 0010:lock_release+0x643/0xa30 kernel/locking/lockdep.c:5875 Code: c7 84 24 90 00 00 00 00 00 00 00 9c 8f 84 24 90 00 00 00 42 80 3c 3b 00 74 08 4c 89 f7 e8 95 1a 8c 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 RSP: 0018:ffffc90000007a40 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 1ffff92000000f5a RCX: ffffc90000007a03 RDX: 0000000000000003 RSI: ffffffff8c2ab6a0 RDI: ffffffff8c80ecc0 RBP: ffffc90000007b70 R08: ffffffff903cdd77 R09: 1ffffffff2079bae R10: dffffc0000000000 R11: fffffbfff2079baf R12: 1ffff92000000f54 R13: 0000000000000046 R14: ffffc90000007ad0 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcb3678e02a CR3: 0000000027144000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x79/0x140 kernel/locking/spinlock.c:194 debug_object_deactivate+0x2d5/0x390 lib/debugobjects.c:888 debug_hrtimer_deactivate kernel/time/hrtimer.c:460 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:502 __run_hrtimer kernel/time/hrtimer.c:1769 [inline] __hrtimer_run_queues+0x305/0xd30 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__preempt_count_add arch/x86/include/asm/preempt.h:79 [inline] RIP: 0010:preempt_count_add+0x3d/0x190 kernel/sched/core.c:5854 Code: c1 e8 03 49 bf 00 00 00 00 00 fc ff df 42 0f b6 04 38 84 c0 0f 85 ed 00 00 00 83 3d 0c 59 d5 18 00 75 07 65 8b 05 0b 76 74 7e <65> 01 1d 04 76 74 7e 48 c7 c0 80 b9 64 9a 48 c1 e8 03 42 0f b6 04 RSP: 0018:ffffc900000d7a98 EFLAGS: 00000246 RAX: 0000000080000000 RBX: 0000000000000001 RCX: ffffffff9a64b903 RDX: 0000000000000000 RSI: ffff88801cedda00 RDI: 0000000000000001 RBP: ffffc900000d7d20 R08: ffffffff8f64f6e3 R09: 1ffffffff1ec9edc R10: dffffc0000000000 R11: fffffbfff1ec9edd R12: 0000000000000000 R13: dffffc0000000000 R14: 0000001cad2697b2 R15: dffffc0000000000 __raw_spin_lock include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock+0x12/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] wg_ratelimiter_gc_entries+0x60/0x470 drivers/net/wireguard/ratelimiter.c:63 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread starved for 10500 jiffies! g8733 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:25784 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6856 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 5904 Comm: udevd Not tainted 6.14.0-rc2-syzkaller-00281-g496659003dac #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1ba4/0x2d30 kernel/smp.c:885 Code: 03 84 c0 75 7e 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 e0 f2 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 90 ee 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00 RSP: 0018:ffffc9000427f4e0 EFLAGS: 00000293 RAX: ffffffff81b5c9d5 RBX: 1ffff110170c8c99 RCX: ffff88806b5cda00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000427f6e0 R08: ffffffff81b5c9a0 R09: 1ffffffff28a890e R10: dffffc0000000000 R11: fffffbfff28a890f R12: ffff8880b873fb48 R13: ffff8880b86464c8 R14: ffff8880b873fb40 R15: 0000000000000000 FS: 00007f2bf4eb0c80(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000564996249440 CR3: 000000007dbfa000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:966 [inline] flush_tlb_mm_range+0x42d/0x710 arch/x86/mm/tlb.c:1054 tlb_flush arch/x86/include/asm/tlb.h:20 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:481 [inline] tlb_flush_mmu+0x1aa/0x680 mm/mmu_gather.c:395 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:488 vms_clear_ptes+0x432/0x530 mm/vma.c:1144 vms_complete_munmap_vmas+0x210/0x8f0 mm/vma.c:1186 do_vmi_align_munmap+0x5ef/0x6f0 mm/vma.c:1445 do_vmi_munmap+0x24e/0x2d0 mm/vma.c:1493 __vm_munmap+0x372/0x510 mm/vma.c:2951 __do_sys_munmap mm/mmap.c:1084 [inline] __se_sys_munmap mm/mmap.c:1081 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1081 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: 0033:0x7f2bf4b1d817 Code: ff ff 76 10 48 8b 15 10 36 0d 00 f7 d8 64 89 02 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 35 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007ffe99ccf0b8 EFLAGS: 00000206 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 000056498a71a5b0 RCX: 00007f2bf4b1d817 RDX: 0000000564996249 RSI: 0000000000906623 RDI: 00007f2bf4000000 RBP: 000056499624dc20 R08: 0000000000000007 R09: ba03a5ff23f1729e R10: 00000000ffffffff R11: 0000000000000206 R12: 000056498a71a5e8 R13: 00007ffe99ccf138 R14: 0000000000000001 R15: 000056499623d910