Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-24 05:02:12 +00:00
Code Issues Packages Projects Releases Wiki Activity

KVM: x86: Handle MPX CPUID adjustment in VMX code

Browse Source 
Move the MPX CPUID adjustments into VMX to eliminate an instance of the
undesirable "unsigned f_* = *_supported ? F(*) : 0" pattern in the
common CPUID handling code.

Note, to maintain existing behavior, VMX must manually check for kernel
support for MPX by querying boot_cpu_has(X86_FEATURE_MPX).  Previously,
do_cpuid_7_mask() masked MPX based on boot_cpu_data by invoking
cpuid_mask() on the associated cpufeatures word, but cpuid_mask() runs
prior to executing vmx_set_supported_cpuid().

No functional change intended.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2020-03-02 15:56:33 -08:00 committed by Paolo Bonzini
parent e745e37d49
commit 6c7ea4b56b
2 changed files with 13 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/x86/kvm/cpuid.c
View File

@ -332,7 +332,6 @@ static int __do_cpuid_func_emulated(struct kvm_cpuid_array *array, u32 func)
static inline void do_cpuid_7_mask(struct kvm_cpuid_entry2 *entry)
{
unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0;
unsigned f_mpx = kvm_mpx_supported() ? F(MPX) : 0;
unsigned f_umip = kvm_x86_ops->umip_emulated() ? F(UMIP) : 0;
unsigned f_intel_pt = kvm_x86_ops->pt_supported() ? F(INTEL_PT) : 0;
unsigned f_la57;
@ -341,7 +340,7 @@ static inline void do_cpuid_7_mask(struct kvm_cpuid_entry2 *entry)
/* cpuid 7.0.ebx */
const u32 kvm_cpuid_7_0_ebx_x86_features =
F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) |
F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) |
F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | 0 /*MPX*/ | F(RDSEED) |
F(ADX) | F(SMAP) | F(AVX512IFMA) | F(AVX512F) | F(AVX512PF) |
F(AVX512ER) | F(AVX512CD) | F(CLFLUSHOPT) | F(CLWB) | F(AVX512DQ) |
F(SHA_NI) | F(AVX512BW) | F(AVX512VL) | f_intel_pt;

14
arch/x86/kvm/vmx/vmx.c
View File

@ -7130,8 +7130,18 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
static void vmx_set_supported_cpuid(struct kvm_cpuid_entry2 *entry)
{
if (entry->function == 1 && nested)
entry->ecx |= feature_bit(VMX);
switch (entry->function) {
case 0x1:
if (nested)
cpuid_entry_set(entry, X86_FEATURE_VMX);
break;
case 0x7:
if (boot_cpu_has(X86_FEATURE_MPX) && kvm_mpx_supported())
cpuid_entry_set(entry, X86_FEATURE_MPX);
break;
default:
break;
}
}
static void vmx_request_immediate_exit(struct kvm_vcpu *vcpu)