Commit fb6d4d34 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: x86: emulate RDPID 



This is encoded as F3 0F C7 /7 with a register argument.  The register
argument is the second array in the group9 GroupDual, while F3 is the
fourth element of a Prefix.

Reviewed-by: default avatarWanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 0367f205

arch/x86/kvm/cpuid.c

+6 −1
Original line number Diff line number Diff line
@@ -293,13 +293,18 @@ static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry, 
{

	switch (func) {

	case 0:

		entry->eax = 1;		/* only one leaf currently */

		entry->eax = 7;

		++*nent;

		break;

	case 1:

		entry->ecx = F(MOVBE);

		++*nent;

		break;

	case 7:

		entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;

		if (index == 0)

			entry->ecx = F(RDPID);

		++*nent;

	default:

		break;

	}

arch/x86/kvm/emulate.c

+21 −1
Original line number Diff line number Diff line
@@ -3514,6 +3514,16 @@ static int em_cwd(struct x86_emulate_ctxt *ctxt) 
	return X86EMUL_CONTINUE;

}



static int em_rdpid(struct x86_emulate_ctxt *ctxt)

{

	u64 tsc_aux = 0;



	if (ctxt->ops->get_msr(ctxt, MSR_TSC_AUX, &tsc_aux))

		return emulate_gp(ctxt, 0);

	ctxt->dst.val = tsc_aux;

	return X86EMUL_CONTINUE;

}



static int em_rdtsc(struct x86_emulate_ctxt *ctxt)

{

	u64 tsc = 0;
@@ -4424,10 +4434,20 @@ static const struct opcode group8[] = { 
	F(DstMem | SrcImmByte | Lock | PageTable,	em_btc),

};



/*

 * The "memory" destination is actually always a register, since we come

 * from the register case of group9.

 */

static const struct gprefix pfx_0f_c7_7 = {

	N, N, N, II(DstMem | ModRM | Op3264 | EmulateOnUD, em_rdpid, rdtscp),

};





static const struct group_dual group9 = { {

	N, I(DstMem64 | Lock | PageTable, em_cmpxchg8b), N, N, N, N, N, N,

}, {

	N, N, N, N, N, N, N, N,

	N, N, N, N, N, N, N,

	GP(0, &pfx_0f_c7_7),

} };



static const struct opcode group11[] = {

arch/x86/kvm/vmx.c

+15 −0
Original line number Diff line number Diff line
@@ -11687,6 +11687,21 @@ static int vmx_check_intercept(struct kvm_vcpu *vcpu, 
			       struct x86_instruction_info *info,

			       enum x86_intercept_stage stage)

{

	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);

	struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;



	/*

	 * RDPID causes #UD if disabled through secondary execution controls.

	 * Because it is marked as EmulateOnUD, we need to intercept it here.

	 */

	if (info->intercept == x86_intercept_rdtscp &&

	    !nested_cpu_has2(vmcs12, SECONDARY_EXEC_RDTSCP)) {

		ctxt->exception.vector = UD_VECTOR;

		ctxt->exception.error_code_valid = false;

		return X86EMUL_PROPAGATE_FAULT;

	}



	/* TODO: check more intercepts... */

	return X86EMUL_CONTINUE;

}