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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
hifive-unleashed-5.1
Linus Torvalds 2018-05-26 13:24:16 -07:00
parent cc71efda82 8ecc4979b1
commit b2096a5e07
2 changed files with 9 additions and 17 deletions
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22
arch/x86/kernel/cpu/common.c
View File

@ -942,12 +942,8 @@ static const __initconst struct x86_cpu_id cpu_no_meltdown[] = {
{}
};
/* Only list CPUs which speculate but are non susceptible to SSB */
static const __initconst struct x86_cpu_id cpu_no_spec_store_bypass[] = {
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_PINEVIEW },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_LINCROFT },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_PENWELL },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_CLOVERVIEW },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_CEDARVIEW },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT1 },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT2 },
@ -955,14 +951,10 @@ static const __initconst struct x86_cpu_id cpu_no_spec_store_bypass[] = {
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_CORE_YONAH },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNL },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNM },
{ X86_VENDOR_CENTAUR, 5, },
{ X86_VENDOR_INTEL, 5, },
{ X86_VENDOR_NSC, 5, },
{ X86_VENDOR_AMD, 0x12, },
{ X86_VENDOR_AMD, 0x11, },
{ X86_VENDOR_AMD, 0x10, },
{ X86_VENDOR_AMD, 0xf, },
{ X86_VENDOR_ANY, 4, },
{}
};
@ -970,6 +962,12 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
{
u64 ia32_cap = 0;
if (x86_match_cpu(cpu_no_speculation))
return;
setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
if (cpu_has(c, X86_FEATURE_ARCH_CAPABILITIES))
rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap);
@ -977,12 +975,6 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
!(ia32_cap & ARCH_CAP_SSB_NO))
setup_force_cpu_bug(X86_BUG_SPEC_STORE_BYPASS);
if (x86_match_cpu(cpu_no_speculation))
return;
setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
if (x86_match_cpu(cpu_no_meltdown))
return;

4
arch/x86/kvm/cpuid.c
View File

@ -407,8 +407,8 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
/* cpuid 7.0.edx*/
const u32 kvm_cpuid_7_0_edx_x86_features =
F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) | F(SSBD) |
F(ARCH_CAPABILITIES);
F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) |
F(SPEC_CTRL_SSBD) | F(ARCH_CAPABILITIES);
/* all calls to cpuid_count() should be made on the same cpu */
get_cpu();