i386: define the 'ssbd' CPUID feature bit (CVE-2018-3639)

New microcode introduces the "Speculative Store Bypass Disable"
CPUID feature bit. This needs to be exposed to guest OS to allow
them to protect against CVE-2018-3639.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Message-Id: <20180521215424.13520-2-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
(cherry picked from commit d19d1f9659)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
This commit is contained in:
Daniel P. Berrangé 2018-05-21 22:54:22 +01:00 committed by Michael Roth
parent ef67e67388
commit 8a302f42a5
2 changed files with 2 additions and 1 deletions

View file

@ -510,7 +510,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, "spec-ctrl", NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, "ssbd",
},
.cpuid_eax = 7,
.cpuid_needs_ecx = true, .cpuid_ecx = 0,

View file

@ -684,6 +684,7 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS];
#define CPUID_7_0_EDX_AVX512_4VNNIW (1U << 2) /* AVX512 Neural Network Instructions */
#define CPUID_7_0_EDX_AVX512_4FMAPS (1U << 3) /* AVX512 Multiply Accumulation Single Precision */
#define CPUID_7_0_EDX_SPEC_CTRL (1U << 26) /* Speculation Control */
#define CPUID_7_0_EDX_SPEC_CTRL_SSBD (1U << 31) /* Speculative Store Bypass Disable */
#define KVM_HINTS_DEDICATED (1U << 0)