diff options
| author | Sean Christopherson <sean.j.christopherson@intel.com> | 2020-03-02 15:57:07 -0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-03-16 17:58:43 +0100 |
| commit | a50718cc3f43f12e6e33b098b5e2a9eb19f13158 (patch) | |
| tree | 6d4cd9dad31fcba4575d551bf4c1fe64643ac4e4 | |
| parent | 91661989d17ccec17bca199e7cb1f463ba4e5b78 (diff) | |
| download | linux-a50718cc3f43f12e6e33b098b5e2a9eb19f13158.tar.bz2 | |
KVM: nSVM: Expose SVM features to L1 iff nested is enabled
Set SVM feature bits in KVM capabilities if and only if nested=true, KVM
shouldn't advertise features that realistically can't be used. Use
kvm_cpu_cap_has(X86_FEATURE_SVM) to indirectly query "nested" in
svm_set_supported_cpuid() in anticipation of moving CPUID 0x8000000A
adjustments into common x86 code.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/svm.c | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 5e3261ec8c59..76a480a37f1d 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1371,21 +1371,21 @@ static __init void svm_set_cpu_caps(void) { kvm_set_cpu_caps(); - /* CPUID 0x80000001 */ - if (nested) + /* CPUID 0x80000001 and 0x8000000A (SVM features) */ + if (nested) { kvm_cpu_cap_set(X86_FEATURE_SVM); + if (boot_cpu_has(X86_FEATURE_NRIPS)) + kvm_cpu_cap_set(X86_FEATURE_NRIPS); + + if (npt_enabled) + kvm_cpu_cap_set(X86_FEATURE_NPT); + } + /* CPUID 0x80000008 */ if (boot_cpu_has(X86_FEATURE_LS_CFG_SSBD) || boot_cpu_has(X86_FEATURE_AMD_SSBD)) kvm_cpu_cap_set(X86_FEATURE_VIRT_SSBD); - - /* CPUID 0x8000000A */ - /* Support next_rip if host supports it */ - kvm_cpu_cap_check_and_set(X86_FEATURE_NRIPS); - - if (npt_enabled) - kvm_cpu_cap_set(X86_FEATURE_NPT); } static __init int svm_hardware_setup(void) @@ -6055,6 +6055,10 @@ static void svm_set_supported_cpuid(struct kvm_cpuid_entry2 *entry) { switch (entry->function) { case 0x8000000A: + if (!kvm_cpu_cap_has(X86_FEATURE_SVM)) { + entry->eax = entry->ebx = entry->ecx = entry->edx = 0; + break; + } entry->eax = 1; /* SVM revision 1 */ entry->ebx = 8; /* Lets support 8 ASIDs in case we add proper ASID emulation to nested SVM */ |