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charset="us-ascii" On Thu, Oct 22, 2026, sashiko-bot@kernel.org wrote: > > diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c > > index 44dad106fad19..945efc1cfaea1 100644 > > --- a/arch/x86/kvm/mmu/tdp_mmu.c > > +++ b/arch/x86/kvm/mmu/tdp_mmu.c > > @@ -1368,7 +1368,7 @@ static bool __kvm_tdp_mmu_age_gfn_range(struct kvm *kvm, > > * this helper must NOT be used to unmap GFNs, as it processes only > > * valid roots! > > */ > > - WARN_ON(types & ~KVM_VALID_ROOTS); > > + WARN_ON_ONCE(types & ~KVM_VALID_ROOTS); > > > > guard(rcu)(); > > for_each_tdp_mmu_root_rcu(kvm, root, range->slot->as_id, types) { > > [Severity: Medium] > Should the WARN_ON() in kvm_mmu_uninit_tdp_mmu() in arch/x86/kvm/mmu/tdp_mmu.c > also be converted to WARN_ON_ONCE()? > > arch/x86/kvm/mmu/tdp_mmu.c:kvm_mmu_uninit_tdp_mmu() { > kvm_tdp_mmu_invalidate_roots(kvm, KVM_VALID_ROOTS); > kvm_tdp_mmu_zap_invalidated_roots(kvm, false); > > #ifdef CONFIG_KVM_PROVE_MMU > KVM_MMU_WARN_ON(atomic64_read(&kvm->arch.tdp_mmu_pages)); > #endif > WARN_ON(!list_empty(&kvm->arch.tdp_mmu_roots)); > ... > } > > Despite having uninit in its name, kvm_mmu_uninit_tdp_mmu() is not a > module-exit helper. When tdp_mmu_enabled is true, it is invoked per VM at > runtime during VM teardown (as well as on the error cleanup path of > kvm_arch_init_vm()): > > kvm_arch_destroy_vm() (in arch/x86/kvm/x86.c) > -> kvm_mmu_uninit_vm() (in arch/x86/kvm/mmu/mmu.c) > -> kvm_mmu_uninit_tdp_mmu() > > Other VM and vCPU teardown checks, such as sev_vm_destroy() and > free_loaded_vmcs(), were converted to WARN_ON_ONCE() in this patch, so > leaving this check unconverted allows repeated warnings on every VM > destruction if kvm->arch.tdp_mmu_roots is non-empty. Gah, yes. For some reason I was thinking that was a module exit function.