KVM: mmu: add missing dirty page tracking cases

We fail to mark a page dirty in three cases:

- setting the accessed bit in a pte
- setting the dirty bit in a pte
- emulating a write into a pagetable

This fix adds the missing cases.

Signed-off-by: Avi Kivity <avi@qumranet.com>
This commit is contained in:
Avi Kivity 2007-02-19 14:37:46 +02:00
parent bb648a0d22
commit bf3f8e86c2

View File

@ -128,8 +128,10 @@ static int FNAME(walk_addr)(struct guest_walker *walker,
goto access_error;
#endif
if (!(*ptep & PT_ACCESSED_MASK))
*ptep |= PT_ACCESSED_MASK; /* avoid rmw */
if (!(*ptep & PT_ACCESSED_MASK)) {
mark_page_dirty(vcpu->kvm, table_gfn);
*ptep |= PT_ACCESSED_MASK;
}
if (walker->level == PT_PAGE_TABLE_LEVEL) {
walker->gfn = (*ptep & PT_BASE_ADDR_MASK)
@ -185,6 +187,12 @@ static void FNAME(release_walker)(struct guest_walker *walker)
kunmap_atomic(walker->table, KM_USER0);
}
static void FNAME(mark_pagetable_dirty)(struct kvm *kvm,
struct guest_walker *walker)
{
mark_page_dirty(kvm, walker->table_gfn[walker->level - 1]);
}
static void FNAME(set_pte)(struct kvm_vcpu *vcpu, u64 guest_pte,
u64 *shadow_pte, u64 access_bits, gfn_t gfn)
{
@ -348,12 +356,15 @@ static int FNAME(fix_write_pf)(struct kvm_vcpu *vcpu,
} else if (kvm_mmu_lookup_page(vcpu, gfn)) {
pgprintk("%s: found shadow page for %lx, marking ro\n",
__FUNCTION__, gfn);
mark_page_dirty(vcpu->kvm, gfn);
FNAME(mark_pagetable_dirty)(vcpu->kvm, walker);
*guest_ent |= PT_DIRTY_MASK;
*write_pt = 1;
return 0;
}
mark_page_dirty(vcpu->kvm, gfn);
*shadow_ent |= PT_WRITABLE_MASK;
FNAME(mark_pagetable_dirty)(vcpu->kvm, walker);
*guest_ent |= PT_DIRTY_MASK;
rmap_add(vcpu, shadow_ent);