summaryrefslogtreecommitdiff
path: root/arch/x86/kvm/svm.c
diff options
context:
space:
mode:
authorSean Christopherson <sean.j.christopherson@intel.com>2020-03-02 15:57:07 -0800
committerPaolo Bonzini <pbonzini@redhat.com>2020-03-16 17:58:43 +0100
commita50718cc3f43f12e6e33b098b5e2a9eb19f13158 (patch)
tree6d4cd9dad31fcba4575d551bf4c1fe64643ac4e4 /arch/x86/kvm/svm.c
parent91661989d17ccec17bca199e7cb1f463ba4e5b78 (diff)
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>
Diffstat (limited to 'arch/x86/kvm/svm.c')
-rw-r--r--arch/x86/kvm/svm.c22
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 */