[PATCH 2/3] KVM: SVM: Handle invpcid during gp interception

[Bandan Das <bsd@redhat.com>]

Use the gp interception path to inject a #UD
to the guest if the guest has invpcid disabled.
This is required because for CPL > 0, #GP takes
precedence over the INVPCID intercept.

Signed-off-by: Bandan Das <bsd@redhat.com>
---
 arch/x86/kvm/svm/svm.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 754e07538b4a..0e8ce7adb815 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -2170,6 +2170,7 @@ enum {
 	SVM_INSTR_VMRUN,
 	SVM_INSTR_VMLOAD,
 	SVM_INSTR_VMSAVE,
+	SVM_INSTR_INVPCID,
 };
 
 /* Return NONE_SVM_INSTR if not SVM instrs, otherwise return decode result */
@@ -2177,6 +2178,8 @@ static int svm_instr_opcode(struct kvm_vcpu *vcpu)
 {
 	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
 
+	if (ctxt->b == 0x82)
+		return SVM_INSTR_INVPCID;
 	if (ctxt->b != 0x1 || ctxt->opcode_len != 2)
 		return NONE_SVM_INSTR;
 
@@ -2200,11 +2203,13 @@ static int emulate_svm_instr(struct kvm_vcpu *vcpu, int opcode)
 		[SVM_INSTR_VMRUN] = SVM_EXIT_VMRUN,
 		[SVM_INSTR_VMLOAD] = SVM_EXIT_VMLOAD,
 		[SVM_INSTR_VMSAVE] = SVM_EXIT_VMSAVE,
+		[SVM_INSTR_INVPCID] = SVM_EXIT_EXCP_BASE + UD_VECTOR,
 	};
 	int (*const svm_instr_handlers[])(struct kvm_vcpu *vcpu) = {
 		[SVM_INSTR_VMRUN] = vmrun_interception,
 		[SVM_INSTR_VMLOAD] = vmload_interception,
 		[SVM_INSTR_VMSAVE] = vmsave_interception,
+		[SVM_INSTR_INVPCID] = ud_interception,
 	};
 	struct vcpu_svm *svm = to_svm(vcpu);
 
@@ -2253,8 +2258,12 @@ static int gp_interception(struct kvm_vcpu *vcpu)
 		if (!is_guest_mode(vcpu))
 			return kvm_emulate_instruction(vcpu,
 				EMULTYPE_VMWARE_GP | EMULTYPE_NO_DECODE);
-	} else
+	} else {
+		if ((opcode == SVM_INSTR_INVPCID) &&
+		    guest_cpuid_has(vcpu, X86_FEATURE_INVPCID))
+			goto reinject;
 		return emulate_svm_instr(vcpu, opcode);
+	}
 
 reinject:
 	kvm_queue_exception_e(vcpu, GP_VECTOR, error_code);
-- 
2.24.1