[PATCH v2 2/6] KVM: x86/mmu: only zap EPT when guest CR0_CD changes

Yan Zhao
2023-05-09T14:16:16Z

Call new helper kvm_zap_gfn_for_memtype() to skip zap mmu if EPT is not
enabled.

Guest CR0_CD value will affect memory type of EPT leaf entry with
noncoherent DMA present. But mmu zap is not necessary if EPT is not
enabled.

Suggested-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
---
arch/x86/kvm/x86.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e7f78fe79b32..ed1e3939bd05 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -942,7 +942,7 @@ void kvm_post_set_cr0(struct kvm_vcpu *vcpu, unsigned long old_cr0, unsigned lon
if (((cr0 ^ old_cr0) & X86_CR0_CD) &&
kvm_arch_has_noncoherent_dma(vcpu->kvm) &&
!kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_CD_NW_CLEARED))
- kvm_zap_gfn_range(vcpu->kvm, 0, ~0ULL);
+ kvm_zap_gfn_for_memtype(vcpu->kvm, gpa_to_gfn(0), gpa_to_gfn(~0ULL));
}
EXPORT_SYMBOL_GPL(kvm_post_set_cr0);

--
2.17.1