Commit e01c2426 authored by Gleb Natapov's avatar Gleb Natapov Committed by Marcelo Tosatti
Browse files

KVM: mark segments accessed on HW task switch 



On HW task switch newly loaded segments should me marked as accessed.

Reported-by: default avatarLorenzo Martignoni <martignlo@gmail.com>
Signed-off-by: default avatarGleb Natapov <gleb@redhat.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 81231c69

arch/x86/kvm/x86.c

+9 −13
Original line number Diff line number Diff line
@@ -4697,18 +4697,6 @@ static u16 get_segment_selector(struct kvm_vcpu *vcpu, int seg) 
	return kvm_seg.selector;

}



static int load_segment_descriptor_to_kvm_desct(struct kvm_vcpu *vcpu,

						u16 selector,

						struct kvm_segment *kvm_seg)

{

	struct desc_struct seg_desc;



	if (load_guest_segment_descriptor(vcpu, selector, &seg_desc))

		return 1;

	seg_desct_to_kvm_desct(&seg_desc, selector, kvm_seg);

	return 0;

}



static int kvm_load_realmode_segment(struct kvm_vcpu *vcpu, u16 selector, int seg)

{

	struct kvm_segment segvar = {
@@ -4749,11 +4737,14 @@ int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, 
				int type_bits, int seg)

{

	struct kvm_segment kvm_seg;

	struct desc_struct seg_desc;



	if (is_vm86_segment(vcpu, seg) || !is_protmode(vcpu))

		return kvm_load_realmode_segment(vcpu, selector, seg);

	if (load_segment_descriptor_to_kvm_desct(vcpu, selector, &kvm_seg))



	if (load_guest_segment_descriptor(vcpu, selector, &seg_desc))

		return 1;

	seg_desct_to_kvm_desct(&seg_desc, selector, &kvm_seg);



	kvm_check_segment_descriptor(vcpu, seg, selector);

	kvm_seg.type |= type_bits;
@@ -4764,6 +4755,11 @@ int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, 
			kvm_seg.unusable = 1;



	kvm_set_segment(vcpu, &kvm_seg, seg);

	if (selector && !kvm_seg.unusable && kvm_seg.s) {

		/* mark segment as accessed */

		seg_desc.type |= 1;

		save_guest_segment_descriptor(vcpu, selector, &seg_desc);

	}

	return 0;

}