commit 7a1638ce4220d52e53d4114e34e4529161a3449c
author Yang Zhang <yang.z.zhang@Intel.com> Mon Aug 05 11:07:13 2013 +0300
committer Paolo Bonzini <pbonzini@redhat.com> Wed Aug 07 15:57:39 2013 +0200
tree dc22f449b34f91acb0c35920a13ab53c8ccc82b7
parent 37406aaaeebc36632efc3f493363da9644e57ef1

nEPT: Redefine EPT-specific link_shadow_page()

Since nEPT doesn't support A/D bit, so we should not set those bit
when build shadow page table.

Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/mmu.c

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 2988df5..68d0f08 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2047,12 +2047,18 @@
 	return __shadow_walk_next(iterator, *iterator->sptep);
 }
 
-static void link_shadow_page(u64 *sptep, struct kvm_mmu_page *sp)
+static void link_shadow_page(u64 *sptep, struct kvm_mmu_page *sp, bool accessed)
 {
 	u64 spte;
 
+	BUILD_BUG_ON(VMX_EPT_READABLE_MASK != PT_PRESENT_MASK ||
+			VMX_EPT_WRITABLE_MASK != PT_WRITABLE_MASK);
+
 	spte = __pa(sp->spt) | PT_PRESENT_MASK | PT_WRITABLE_MASK |
-	       shadow_user_mask | shadow_x_mask | shadow_accessed_mask;
+	       shadow_user_mask | shadow_x_mask;
+
+	if (accessed)
+		spte |= shadow_accessed_mask;
 
 	mmu_spte_set(sptep, spte);
 }
@@ -2677,7 +2683,7 @@
 					      iterator.level - 1,
 					      1, ACC_ALL, iterator.sptep);
 
-			link_shadow_page(iterator.sptep, sp);
+			link_shadow_page(iterator.sptep, sp, true);
 		}
 	}
 	return emulate;

arch/x86/kvm/paging_tmpl.h

diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 8937688..50b8679 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -555,7 +555,7 @@
 			goto out_gpte_changed;
 
 		if (sp)
-			link_shadow_page(it.sptep, sp);
+			link_shadow_page(it.sptep, sp, PT_GUEST_ACCESSED_MASK);
 	}
 
 	for (;
@@ -575,7 +575,7 @@
 
 		sp = kvm_mmu_get_page(vcpu, direct_gfn, addr, it.level-1,
 				      true, direct_access, it.sptep);
-		link_shadow_page(it.sptep, sp);
+		link_shadow_page(it.sptep, sp, PT_GUEST_ACCESSED_MASK);
 	}
 
 	clear_sp_write_flooding_count(it.sptep);