From b64b3763a5b3868e85330c891e1a30189dcde9b1 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Thu, 31 May 2007 18:24:09 +0300 Subject: [PATCH] KVM: MMU: Don't cache guest access bits in the shadow page table This was once used to avoid accessing the guest pte when upgrading the shadow pte from read-only to read-write. But usually we need to set the guest pte dirty or accessed bits anyway, so this wasn't really exploited. Signed-off-by: Avi Kivity --- drivers/kvm/mmu.c | 8 -------- drivers/kvm/paging_tmpl.h | 1 - 2 files changed, 9 deletions(-) diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c index b47391ffe5..986d01294f 100644 --- a/drivers/kvm/mmu.c +++ b/drivers/kvm/mmu.c @@ -97,14 +97,6 @@ static int dbg = 1; #define PT_SHADOW_PS_MARK (1ULL << PT_FIRST_AVAIL_BITS_SHIFT) #define PT_SHADOW_IO_MARK (1ULL << PT_FIRST_AVAIL_BITS_SHIFT) -#define PT_SHADOW_WRITABLE_SHIFT (PT_FIRST_AVAIL_BITS_SHIFT + 1) -#define PT_SHADOW_WRITABLE_MASK (1ULL << PT_SHADOW_WRITABLE_SHIFT) - -#define PT_SHADOW_USER_SHIFT (PT_SHADOW_WRITABLE_SHIFT + 1) -#define PT_SHADOW_USER_MASK (1ULL << (PT_SHADOW_USER_SHIFT)) - -#define PT_SHADOW_BITS_OFFSET (PT_SHADOW_WRITABLE_SHIFT - PT_WRITABLE_SHIFT) - #define VALID_PAGE(x) ((x) != INVALID_PAGE) #define PT64_LEVEL_BITS 9 diff --git a/drivers/kvm/paging_tmpl.h b/drivers/kvm/paging_tmpl.h index b17a4b783c..adc1206cf6 100644 --- a/drivers/kvm/paging_tmpl.h +++ b/drivers/kvm/paging_tmpl.h @@ -219,7 +219,6 @@ static void FNAME(set_pte_common)(struct kvm_vcpu *vcpu, spte |= PT_PRESENT_MASK | PT_ACCESSED_MASK | PT_DIRTY_MASK; spte |= *gpte & PT64_NX_MASK; - spte |= access_bits << PT_SHADOW_BITS_OFFSET; if (!dirty) access_bits &= ~PT_WRITABLE_MASK; -- 2.39.5