[PATCH 16/16] KVM: x86/mmu: WARN if root_hpa is invalid when handling a page fault

From: Sean Christopherson
Date: Fri Dec 06 2019 - 18:57:47 EST


WARN if root_hpa is invalid when handling a page fault. The check on
root_hpa exists for historical reasons that no longer apply to the
current KVM code base.

Remove an equivalent debug-only warning in direct_page_fault(), whose
existence more or less confirms that root_hpa should always be valid
when handling a page fault.

Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
---
arch/x86/kvm/mmu/mmu.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 88fd1022731f..32534ea1efd0 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4168,8 +4168,6 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
kvm_pfn_t pfn;
int level, r;

- MMU_WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root_hpa));
-
if (page_fault_handle_page_track(vcpu, error_code, gfn))
return RET_PF_EMULATE;

@@ -5459,7 +5457,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
int r, emulation_type = 0;
bool direct = vcpu->arch.mmu->direct_map;

- if (!VALID_PAGE(vcpu->arch.mmu->root_hpa))
+ if (WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root_hpa)))
return RET_PF_RETRY;

/* With shadow page tables, fault_address contains a GVA or nGPA. */
--
2.24.0