From f3b8c964a9a6cfef6d3ca778648d53947b9fd257 Mon Sep 17 00:00:00 2001 From: Gui Jianfeng Date: Wed, 5 May 2010 09:09:21 +0800 Subject: [PATCH] KVM: MMU: mark page table dirty when a pte is actually modified Sometime cmpxchg_gpte doesn't modify gpte, in such case, don't mark page table page as dirty. Signed-off-by: Gui Jianfeng Signed-off-by: Avi Kivity --- arch/x86/kvm/paging_tmpl.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index c7f2777..5c8ac06 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -177,10 +177,10 @@ walk: if (!(pte & PT_ACCESSED_MASK)) { trace_kvm_mmu_set_accessed_bit(table_gfn, index, sizeof(pte)); - mark_page_dirty(vcpu->kvm, table_gfn); if (FNAME(cmpxchg_gpte)(vcpu->kvm, table_gfn, index, pte, pte|PT_ACCESSED_MASK)) goto walk; + mark_page_dirty(vcpu->kvm, table_gfn); pte |= PT_ACCESSED_MASK; } @@ -217,11 +217,11 @@ walk: bool ret; trace_kvm_mmu_set_dirty_bit(table_gfn, index, sizeof(pte)); - mark_page_dirty(vcpu->kvm, table_gfn); ret = FNAME(cmpxchg_gpte)(vcpu->kvm, table_gfn, index, pte, pte|PT_DIRTY_MASK); if (ret) goto walk; + mark_page_dirty(vcpu->kvm, table_gfn); pte |= PT_DIRTY_MASK; walker->ptes[walker->level - 1] = pte; } -- 2.7.4