KVM: SVM: Report emulated SVM features to userspace

This patch implements the reporting of the emulated SVM
features to userspace instead of the real hardware
capabilities. Every real hardware capability needs emulation
in nested svm so the old behavior was broken.

Cc: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 0fa2035bd8e7..65fc11438b75 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3154,6 +3154,16 @@ static void svm_cpuid_update(struct kvm_vcpu *vcpu)
 
 static void svm_set_supported_cpuid(u32 func, struct kvm_cpuid_entry2 *entry)
 {
+        switch (func) {
+        case 0x8000000A:
+                entry->eax = 1; /* SVM revision 1 */
+                entry->ebx = 8; /* Lets support 8 ASIDs in case we add proper
+                                   ASID emulation to nested SVM */
+                entry->ecx = 0; /* Reserved */
+                entry->edx = 0; /* Do not support any additional features */
+
+                break;
+        }
 }
 
 static const struct trace_print_flags svm_exit_reasons_str[] = {