From: jsg <jsg@openbsd.org>
Date: Wed, 16 Aug 2023 07:26:05 +0000 (+0000)
Subject: avoid patch level msr on amd families < 0fh
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=92db83438c54a3da7528d3fa9a5b6ca529dff655;p=openbsd

avoid patch level msr on amd families < 0fh

Paul de Weerd reported it isn't implemented on ALIX with
cpu0: Geode(TM) Integrated Processor by AMD PCS ("AuthenticAMD" 586-class) 499 MHz, 05-0a-02

the earliest amd microcode update files I can find are for family 0fh (K8)

ok guenther@
---

diff --git a/sys/arch/i386/i386/machdep.c b/sys/arch/i386/i386/machdep.c
index 8f943685c82..7bbefdfcd6c 100644
--- a/sys/arch/i386/i386/machdep.c
+++ b/sys/arch/i386/i386/machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: machdep.c,v 1.666 2023/08/09 00:01:44 jsg Exp $	*/
+/*	$OpenBSD: machdep.c,v 1.667 2023/08/16 07:26:05 jsg Exp $	*/
 /*	$NetBSD: machdep.c,v 1.214 1996/11/10 03:16:17 thorpej Exp $	*/
 
 /*-
@@ -1863,7 +1863,8 @@ identifycpu(struct cpu_info *ci)
 		uint64_t level = 0;
 		uint32_t dummy;
 
-		if (strcmp(cpu_vendor, "AuthenticAMD") == 0) {
+		if (strcmp(cpu_vendor, "AuthenticAMD") == 0 &&
+		    ci->ci_family >= 0x0f) {
 			level = rdmsr(MSR_PATCH_LEVEL);
 		} else if (strcmp(cpu_vendor, "GenuineIntel") == 0) {
 			wrmsr(MSR_BIOS_SIGN, 0);