x86/sev-es: Wire up existing #VC exit-code handlers

Re-use the handlers for CPUID- and IOIO-caused #VC exceptions in the
early boot handler.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200907131613.12703-48-joro@8bytes.org

arch/x86/kernel/sev-es-shared.c

@@ -325,8 +325,7 @@ static enum es_result vc_ioio_exitinfo(struct es_em_ctxt *ctxt, u64 *exitinfo)
 	return ES_OK;
 }
 
-static enum es_result __maybe_unused
-vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
+static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
 {
 	struct pt_regs *regs = ctxt->regs;
 	u64 exit_info_1, exit_info_2;
@@ -434,8 +433,8 @@ vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
 	return ret;
 }
 
-static enum es_result __maybe_unused vc_handle_cpuid(struct ghcb *ghcb,
-						     struct es_em_ctxt *ctxt)
+static enum es_result vc_handle_cpuid(struct ghcb *ghcb,
+				      struct es_em_ctxt *ctxt)
 {
 	struct pt_regs *regs = ctxt->regs;
 	u32 cr4 = native_read_cr4();

arch/x86/kernel/sev-es.c

@@ -441,6 +441,12 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
 	enum es_result result;
 
 	switch (exit_code) {
+	case SVM_EXIT_CPUID:
+		result = vc_handle_cpuid(ghcb, ctxt);
+		break;
+	case SVM_EXIT_IOIO:
+		result = vc_handle_ioio(ghcb, ctxt);
+		break;
 	default:
 		/*
 		 * Unexpected #VC exception