Commit cb84b55f authored by Marcelo Tosatti's avatar Marcelo Tosatti
Browse files

KVM: x86: raise TSS exception for NULL CS and SS segments 



Windows 2003 uses task switch to triple fault and reboot (the other
exception being reserved pdptrs bits).

Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 3fd28fce

arch/x86/kvm/x86.c

+11 −0
Original line number Diff line number Diff line
@@ -4410,6 +4410,15 @@ static int is_vm86_segment(struct kvm_vcpu *vcpu, int seg) 
		(kvm_get_rflags(vcpu) & X86_EFLAGS_VM);

}



static void kvm_check_segment_descriptor(struct kvm_vcpu *vcpu, int seg,

					 u16 selector)

{

	/* NULL selector is not valid for CS and SS */

	if (seg == VCPU_SREG_CS || seg == VCPU_SREG_SS)

		if (!selector)

			kvm_queue_exception_e(vcpu, TS_VECTOR, selector >> 3);

}



int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,

				int type_bits, int seg)

{
@@ -4419,6 +4428,8 @@ int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, 
		return kvm_load_realmode_segment(vcpu, selector, seg);

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

		return 1;



	kvm_check_segment_descriptor(vcpu, seg, selector);

	kvm_seg.type |= type_bits;



	if (seg != VCPU_SREG_SS && seg != VCPU_SREG_CS &&