rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=599c/1/0x4000000000000000 softirq=121661/121662 fqs=45 rcu: (detected by 1, t=10506 jiffies, g=107753, q=148 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 21465 Comm: syz.3.4199 Not tainted 6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] RIP: 0010:_raw_spin_lock_irq+0x9d/0xf0 kernel/locking/spinlock.c:170 Code: 02 00 00 74 05 e8 53 2f 66 f6 bf 01 00 00 00 e8 a9 17 2f f6 48 8d 7b 18 31 f6 31 d2 31 c9 41 b8 01 00 00 00 45 31 c9 ff 75 08 8e 76 3c f6 48 83 c4 08 48 89 df e8 e2 1a 3d f6 48 c7 04 24 0e RSP: 0018:ffffc90000007c98 EFLAGS: 00000046 RAX: 0000000000010002 RBX: ffff8880b8627ac0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880b8627ad8 RBP: ffffc90000007d30 R08: 0000000000000001 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1f3fc7f R12: ffff888027af3340 R13: dffffc0000000000 R14: 1ffff92000000f94 R15: dffffc0000000000 FS: 00007f2da6ba56c0(0000) GS:ffff888125c85000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d317ff8 CR3: 0000000057e80000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1765 [inline] __hrtimer_run_queues+0x602/0xc60 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 2b 7e fb 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000f087518 EFLAGS: 00000206 RAX: ffc700cffef93f00 RBX: 0000000000000000 RCX: ffc700cffef93f00 RDX: 0000000000000000 RSI: ffffffff8db5a88e RDI: ffffffff8be1b800 RBP: ffffffff820e8cbe R08: 0000000000000000 R09: ffffffff820e8cbe R10: dffffc0000000000 R11: fffff9400000a261 R12: 0000000000000000 R13: ffff88801a47b078 R14: 0000000000000001 R15: 0000000000000246 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] __pte_offset_map_lock+0x13e/0x210 mm/pgtable-generic.c:402 get_locked_pte include/linux/mm.h:2703 [inline] __text_poke+0x2e6/0xa10 arch/x86/kernel/alternative.c:2505 text_poke arch/x86/kernel/alternative.c:2590 [inline] smp_text_poke_batch_finish+0xd0a/0x1100 arch/x86/kernel/alternative.c:2979 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_slow_inc_cpuslocked+0x80/0xf0 kernel/jump_label.c:168 static_key_slow_inc+0x1a/0x30 kernel/jump_label.c:191 kvm_create_lapic+0x110/0x400 arch/x86/kvm/lapic.c:2914 kvm_arch_vcpu_create+0x1ec/0x920 arch/x86/kvm/x86.c:12348 kvm_vm_ioctl_create_vcpu+0x429/0x930 virt/kvm/kvm_main.c:4192 kvm_vm_ioctl+0x7f7/0xc60 virt/kvm/kvm_main.c:5138 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2da5d8e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2da6ba5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f2da5fb5fa0 RCX: 00007f2da5d8e929 RDX: 0000000000000000 RSI: 000000000000ae41 RDI: 0000000000000008 RBP: 00007f2da5e10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2da5fb5fa0 R15: 00007ffd6b2539f8 rcu: rcu_preempt kthread starved for 10200 jiffies! g107753 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:27000 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 20194 Comm: udevd Not tainted 6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0xf6e/0x12d0 kernel/smp.c:885 Code: 89 ee 83 e6 01 31 ff e8 60 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 0b 74 0b 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 07 01 00 00 00 74 1e e8 f0 73 0b 00 eb e5 44 89 RSP: 0018:ffffc9000bbd7580 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b873c9c0 RCX: ffff888027628000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000bbd76e0 R08: ffffffff8f9fe3f7 R09: 1ffffffff1f3fc7e R10: dffffc0000000000 R11: fffffbfff1f3fc7f R12: 1ffff110170c868d R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8643468 FS: 00007fe9a61d4880(0000) GS:ffff888125d85000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb10f6d04fe CR3: 00000000539e4000 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:1361 [inline] flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline] tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497 vms_clear_ptes+0x42c/0x540 mm/vma.c:1230 vms_complete_munmap_vmas+0x206/0x8a0 mm/vma.c:1272 do_vmi_align_munmap+0x358/0x420 mm/vma.c:1531 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1579 __vm_munmap+0x23b/0x3d0 mm/vma.c:3108 __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/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe9a5b1e097 Code: 73 01 c3 48 8b 0d 61 2d 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 31 2d 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007ffdd9392298 EFLAGS: 00000206 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 00005560dc768bf0 RCX: 00007fe9a5b1e097 RDX: 0000000000000000 RSI: 00000000009480e8 RDI: 00007fe9a5000000 RBP: 00005560dc768910 R08: 00005560dc77b110 R09: 0000000000000006 R10: 0000000000000000 R11: 0000000000000206 R12: 00005560bef07588 R13: 00007ffdd9392320 R14: 0000000000000000 R15: 0000000000000000