Messages in this thread Patch in this message | | | Date | Wed, 15 Jan 2014 12:10:56 +0100 | From | Borislav Petkov <> | Subject | [PATCH -v1.2] x86, CPU, AMD: Add workaround for family 16h, erratum 793 |
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On Tue, Jan 14, 2014 at 04:38:27PM -0800, H. Peter Anvin wrote: > In file included from > /home/hpa/kernel/distwork/arch/x86/include/asm/processor.h:20:0,
Finnish!
Well, Boris the dumbass forgot to amend, changes were still in the index but not committed. This is what I get when I do a couple of things at the same time. :(
--- From: Borislav Petkov <bp@suse.de>
This adds the workaround for erratum 793 as a precaution in case not every BIOS implements it. This addresses CVE-2013-6885.
Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@amd.com> --- arch/x86/include/uapi/asm/msr-index.h | 1 + arch/x86/kernel/cpu/amd.c | 10 ++++++++++ 2 files changed, 11 insertions(+)
diff --git a/arch/x86/include/uapi/asm/msr-index.h b/arch/x86/include/uapi/asm/msr-index.h index 37813b5ddc37..59cea185ad1d 100644 --- a/arch/x86/include/uapi/asm/msr-index.h +++ b/arch/x86/include/uapi/asm/msr-index.h @@ -184,6 +184,7 @@ #define MSR_AMD64_PATCH_LOADER 0xc0010020 #define MSR_AMD64_OSVW_ID_LENGTH 0xc0010140 #define MSR_AMD64_OSVW_STATUS 0xc0010141 +#define MSR_AMD64_LS_CFG 0xc0011020 #define MSR_AMD64_DC_CFG 0xc0011022 #define MSR_AMD64_BU_CFG2 0xc001102a #define MSR_AMD64_IBSFETCHCTL 0xc0011030 diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 4a48e8bbd857..6ac3a67ad471 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -507,6 +507,16 @@ static void early_init_amd(struct cpuinfo_x86 *c) set_cpu_cap(c, X86_FEATURE_EXTD_APICID); } #endif + + /* F16h erratum 793, CVE-2013-6885 */ + if (c->x86 == 0x16 && c->x86_model <= 0xf) { + u64 val; + + rdmsrl(MSR_AMD64_LS_CFG, val); + if (!(val & BIT(15))) + wrmsrl(MSR_AMD64_LS_CFG, val | BIT(15)); + } + } static const int amd_erratum_383[]; -- 1.8.5.2.192.g7794a68
-- Regards/Gruss, Boris.
Sent from a fat crate under my desk. Formatting is fine. --
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