Module Name: src
Committed By: maxv
Date: Sat Nov 10 10:52:52 UTC 2018
Modified Files:
src/sys/arch/x86/include: specialreg.h
src/sys/arch/x86/x86: identcpu.c
Log Message:
Declare the MSR_VIA_ACE values as macros, and use a consistent naming,
similar to the rest of the file.
I'm wondering if I'm not fixing a huge bug here. The ECX8 value we were
using was wrong: ECX8 is bit 1, not bit 0. Bit 0 is ALTINST, an alternate
ISA, which is now known to be backdoored.
So it looks like we were explicitly enabling the backdoor.
Not tested, because I don't have a VIA cpu.
To generate a diff of this commit:
cvs rdiff -u -r1.130 -r1.131 src/sys/arch/x86/include/specialreg.h
cvs rdiff -u -r1.80 -r1.81 src/sys/arch/x86/x86/identcpu.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/x86/include/specialreg.h
diff -u src/sys/arch/x86/include/specialreg.h:1.130 src/sys/arch/x86/include/specialreg.h:1.131
--- src/sys/arch/x86/include/specialreg.h:1.130 Mon Aug 20 08:53:48 2018
+++ src/sys/arch/x86/include/specialreg.h Sat Nov 10 10:52:51 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: specialreg.h,v 1.130 2018/08/20 08:53:48 msaitoh Exp $ */
+/* $NetBSD: specialreg.h,v 1.131 2018/11/10 10:52:51 maxv Exp $ */
/*-
* Copyright (c) 1991 The Regents of the University of California.
@@ -796,7 +796,9 @@
#define MSR_VIA_RNG_NOISE_B 0x00000100
#define MSR_VIA_RNG_2NOISE 0x00000300
#define MSR_VIA_ACE 0x00001107
-#define MSR_VIA_ACE_ENABLE 0x10000000
+#define VIA_ACE_ALTINST 0x00000001
+#define VIA_ACE_ECX8 0x00000002
+#define VIA_ACE_ENABLE 0x10000000
/*
* VIA "Eden" MSRs
Index: src/sys/arch/x86/x86/identcpu.c
diff -u src/sys/arch/x86/x86/identcpu.c:1.80 src/sys/arch/x86/x86/identcpu.c:1.81
--- src/sys/arch/x86/x86/identcpu.c:1.80 Sat Nov 10 09:42:42 2018
+++ src/sys/arch/x86/x86/identcpu.c Sat Nov 10 10:52:52 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: identcpu.c,v 1.80 2018/11/10 09:42:42 maxv Exp $ */
+/* $NetBSD: identcpu.c,v 1.81 2018/11/10 10:52:52 maxv Exp $ */
/*-
* Copyright (c) 1999, 2000, 2001, 2006, 2007, 2008 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: identcpu.c,v 1.80 2018/11/10 09:42:42 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: identcpu.c,v 1.81 2018/11/10 10:52:52 maxv Exp $");
#include "opt_xen.h"
@@ -505,7 +505,7 @@ cpu_probe_winchip(struct cpu_info *ci)
* bit in the FCR MSR.
*/
ci->ci_feat_val[0] |= CPUID_CX8;
- wrmsr(MSR_VIA_FCR, rdmsr(MSR_VIA_FCR) | 0x00000001);
+ wrmsr(MSR_VIA_FCR, rdmsr(MSR_VIA_FCR) | VIA_ACE_ECX8);
break;
}
}
@@ -598,9 +598,8 @@ cpu_probe_c3(struct cpu_info *ci)
if (ace_enable) {
msr = rdmsr(MSR_VIA_ACE);
- wrmsr(MSR_VIA_ACE, msr | MSR_VIA_ACE_ENABLE);
+ wrmsr(MSR_VIA_ACE, msr | VIA_ACE_ENABLE);
}
-
}
}
