Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 store buffer fixes from Thomas Gleixner:
"Two fixes for the SSBD mitigation code:
- expose SSBD properly to guests. This got broken when the CPU
feature flags got reshuffled.
- simplify the CPU detection logic to avoid duplicate entries in the
tables"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation: Simplify the CPU bug detection logic
KVM/VMX: Expose SSBD properly to guests
+9
-17
+7
-15
arch/x86/kernel/cpu/common.c
+7
-15
arch/x86/kernel/cpu/common.c
···
942
942
{}
943
943
};
944
944
945
+
/* Only list CPUs which speculate but are non susceptible to SSB */
945
946
static const __initconst struct x86_cpu_id cpu_no_spec_store_bypass[] = {
946
-
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_PINEVIEW },
947
-
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_LINCROFT },
948
-
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_PENWELL },
949
-
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_CLOVERVIEW },
950
-
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_CEDARVIEW },
951
947
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT1 },
952
948
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT },
953
949
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT2 },
···
951
955
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_CORE_YONAH },
952
956
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNL },
953
957
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNM },
954
-
{ X86_VENDOR_CENTAUR, 5, },
955
-
{ X86_VENDOR_INTEL, 5, },
956
-
{ X86_VENDOR_NSC, 5, },
957
958
{ X86_VENDOR_AMD, 0x12, },
958
959
{ X86_VENDOR_AMD, 0x11, },
959
960
{ X86_VENDOR_AMD, 0x10, },
960
961
{ X86_VENDOR_AMD, 0xf, },
961
-
{ X86_VENDOR_ANY, 4, },
962
962
{}
963
963
};
964
964
···
962
970
{
963
971
u64 ia32_cap = 0;
964
972
973
+
if (x86_match_cpu(cpu_no_speculation))
974
+
return;
975
+
976
+
setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
977
+
setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
978
+
965
979
if (cpu_has(c, X86_FEATURE_ARCH_CAPABILITIES))
966
980
rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap);
967
981
968
982
if (!x86_match_cpu(cpu_no_spec_store_bypass) &&
969
983
!(ia32_cap & ARCH_CAP_SSB_NO))
970
984
setup_force_cpu_bug(X86_BUG_SPEC_STORE_BYPASS);
971
-
972
-
if (x86_match_cpu(cpu_no_speculation))
973
-
return;
974
-
975
-
setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
976
-
setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
977
985
978
986
if (x86_match_cpu(cpu_no_meltdown))
979
987
return;
+2
-2
arch/x86/kvm/cpuid.c
+2
-2
arch/x86/kvm/cpuid.c
···
407
407
408
408
/* cpuid 7.0.edx*/
409
409
const u32 kvm_cpuid_7_0_edx_x86_features =
410
-
F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) | F(SSBD) |
411
-
F(ARCH_CAPABILITIES);
410
+
F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) |
411
+
F(SPEC_CTRL_SSBD) | F(ARCH_CAPABILITIES);
412
412
413
413
/* all calls to cpuid_count() should be made on the same cpu */
414
414
get_cpu();