KVM: MIPS: Add guest exit exception callback

Add a callback for MIPS KVM implementations to handle the VZ guest
exit exception. Currently the trap & emulate implementation contains a
stub which reports an internal error, but the callback will be used
properly by the VZ implementation.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org

arch/mips/kvm/mips.c

@@ -1348,6 +1348,11 @@ int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
 		break;
 
+	case EXCCODE_GE:
+		/* defer exit accounting to handler */
+		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
+		break;
+
 	default:
 		if (cause & CAUSEF_BD)
 			opc += 1;