KVM: MMU: Don't flush shadow when enabling dirty tracking
Instead, drop large mappings, which were the reason we dropped shadow.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index f02b8ed..ccacf0b 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3538,14 +3538,18 @@
if (!test_bit(slot, sp->slot_bitmap))
continue;
- if (sp->role.level != PT_PAGE_TABLE_LEVEL)
- continue;
-
pt = sp->spt;
- for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
+ for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
+ if (sp->role.level != PT_PAGE_TABLE_LEVEL
+ && is_large_pte(pt[i])) {
+ drop_spte(kvm, &pt[i],
+ shadow_trap_nonpresent_pte);
+ --kvm->stat.lpages;
+ }
/* avoid RMW */
if (is_writable_pte(pt[i]))
update_spte(&pt[i], pt[i] & ~PT_WRITABLE_MASK);
+ }
}
kvm_flush_remote_tlbs(kvm);
}