KVM: MMU: do not record gfn in kvm_mmu_pte_write
No need to record the gfn to verifier the pte has the same mode as
current vcpu, it's because we only speculatively update the pte only
if the pte and vcpu have the same mode
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index d5455b1..91a1946 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3228,7 +3228,6 @@
kvm_release_pfn_clean(pfn);
return;
}
- vcpu->arch.update_pte.gfn = gfn;
vcpu->arch.update_pte.pfn = pfn;
}
@@ -3275,9 +3274,8 @@
/*
* Assume that the pte write on a page table of the same type
- * as the current vcpu paging mode. This is nearly always true
- * (might be false while changing modes). Note it is verified later
- * by update_pte().
+ * as the current vcpu paging mode since we update the sptes only
+ * when they have the same mode.
*/
if ((is_pae(vcpu) && bytes == 4) || !new) {
/* Handle a 32-bit guest writing two halves of a 64-bit gpte */