Commit 98899aa0 authored by Marcelo Tosatti's avatar Marcelo Tosatti Committed by Avi Kivity
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KVM: task switch: segment base is linear address 



The segment base is always a linear address, so translate before
accessing guest memory.

Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 5f4cb662

arch/x86/kvm/x86.c

+9 −3
Original line number Diff line number Diff line
@@ -3223,6 +3223,7 @@ static void get_segment_descritptor_dtable(struct kvm_vcpu *vcpu, 
static int load_guest_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,

					 struct desc_struct *seg_desc)

{

	gpa_t gpa;

	struct descriptor_table dtable;

	u16 index = selector >> 3;
@@ -3232,13 +3233,16 @@ static int load_guest_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, 
		kvm_queue_exception_e(vcpu, GP_VECTOR, selector & 0xfffc);

		return 1;

	}

	return kvm_read_guest(vcpu->kvm, dtable.base + index * 8, seg_desc, 8);

	gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, dtable.base);

	gpa += index * 8;

	return kvm_read_guest(vcpu->kvm, gpa, seg_desc, 8);

}



/* allowed just for 8 bytes segments */

static int save_guest_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,

					 struct desc_struct *seg_desc)

{

	gpa_t gpa;

	struct descriptor_table dtable;

	u16 index = selector >> 3;
@@ -3246,7 +3250,9 @@ static int save_guest_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, 


	if (dtable.limit < index * 8 + 7)

		return 1;

	return kvm_write_guest(vcpu->kvm, dtable.base + index * 8, seg_desc, 8);

	gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, dtable.base);

	gpa += index * 8;

	return kvm_write_guest(vcpu->kvm, gpa, seg_desc, 8);

}



static u32 get_tss_base_addr(struct kvm_vcpu *vcpu,
@@ -3258,7 +3264,7 @@ static u32 get_tss_base_addr(struct kvm_vcpu *vcpu, 
	base_addr |= (seg_desc->base1 << 16);

	base_addr |= (seg_desc->base2 << 24);



	return base_addr;

	return vcpu->arch.mmu.gva_to_gpa(vcpu, base_addr);

}



static int load_tss_segment32(struct kvm_vcpu *vcpu,