Only remove write access in the last sptes
Signed-off-by: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxx>
---
arch/x86/kvm/mmu.c | 9 +++++++--
1 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index b6a9963..b9bf016 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3540,12 +3540,17 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot)
pt = sp->spt;
for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
- if (sp->role.level != PT_PAGE_TABLE_LEVEL
- && is_large_pte(pt[i])) {
+ if (!is_shadow_present_pte(pt[i]) ||
+ !is_last_spte(pt[i], sp->role.level))
+ continue;
+
+ if (is_large_pte(pt[i])) {
drop_spte(kvm, &pt[i],
shadow_trap_nonpresent_pte);
--kvm->stat.lpages;
+ continue;
}
+
/* avoid RMW */
if (is_writable_pte(pt[i]))
update_spte(&pt[i], pt[i] & ~PT_WRITABLE_MASK);
--
1.7.4
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