That is quite a large hammer. It would be preferable to
find out which msr it objects to and guard it with a specific cpuid
check, and/or fix the hypervisor.
On Mon, May 20, 2013 at 10:34:43AM +0300, Roman Kravchuk wrote:
> patch_amd64errata.diff
>
> Index: amd64/amd64/amd64errata.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/amd64/amd64/amd64errata.c,v
> retrieving revision 1.3
> diff -u -p -u -p -r1.3 amd64errata.c
> --- amd64/amd64/amd64errata.c 27 Mar 2012 05:59:46 -0000 1.3
> +++ amd64/amd64/amd64errata.c 19 May 2013 23:48:11 -0000
> @@ -293,6 +293,9 @@ amd64_errata(struct cpu_info *ci)
> int found = 0;
> int corrected = 0;
>
> + if (ci->ci_feature_eflags & CPUIDECX_RAZ)
> + return;
> +
> CPUID(0x80000001, code, dummy, dummy, dummy);
>
> for (i = 0; ; i += 2) {
> Index: amd64/amd64/identcpu.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/amd64/amd64/identcpu.c,v
> retrieving revision 1.47
> diff -u -p -u -p -r1.47 identcpu.c
> --- amd64/amd64/identcpu.c 6 May 2013 04:32:12 -0000 1.47
> +++ amd64/amd64/identcpu.c 19 May 2013 23:48:11 -0000
> @@ -129,6 +129,7 @@ const struct {
> { CPUIDECX_AVX, "AVX" },
> { CPUIDECX_F16C, "F16C" },
> { CPUIDECX_RDRAND, "RDRAND" },
> + { CPUIDECX_RAZ, "RAZ" }
> }, cpu_ecpuid_ecxfeatures[] = {
> { CPUIDECX_LAHF, "LAHF" },
> { CPUIDECX_CMPLEG, "CMPLEG" },
> Index: amd64/include/specialreg.h
> ===================================================================
> RCS file: /cvs/src/sys/arch/amd64/include/specialreg.h,v
> retrieving revision 1.25
> diff -u -p -u -p -r1.25 specialreg.h
> --- amd64/include/specialreg.h 6 May 2013 04:32:12 -0000 1.25
> +++ amd64/include/specialreg.h 19 May 2013 23:48:11 -0000
> @@ -158,6 +158,7 @@
> #define CPUIDECX_AVX 0x10000000 /* Advanced Vector Extensions */
> #define CPUIDECX_F16C 0x20000000 /* 16bit fp conversion */
> #define CPUIDECX_RDRAND 0x40000000 /* RDRAND instruction */
> +#define CPUIDECX_RAZ 0x80000000 /* RAZ. Indicates guest state. */
>
> /*
> * "Structured Extended Feature Flags Parameters" (CPUID function 0x7,
> leaf 0)
