i386/tdx: Wire CPU features up with attributes of TD guest

For QEMU VMs,
  - PKS is configured via CPUID_7_0_ECX_PKS, e.g., -cpu xxx,+pks  and
  - PMU is configured by x86cpu->enable_pmu, e.g., -cpu xxx,pmu=on

While the bit 30 (PKS) and bit 63 (PERFMON) of TD's attributes are also
used to configure the PKS and PERFMON/PMU of TD, reuse the existing
configuration interfaces of 'cpu' for TD's attributes.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250508150002.689633-12-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index a30731b1a3b4c25ddb9d29719ca509d03f1cf4b5..22d66bdb14f2b74fe4a2b33891541c6cd6a3c215 100644 (file)
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -19,6 +19,8 @@
 #include "tdx.h"
 
 #define TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE   BIT_ULL(28)
+#define TDX_TD_ATTRIBUTES_PKS               BIT_ULL(30)
+#define TDX_TD_ATTRIBUTES_PERFMON           BIT_ULL(63)
 
 static TdxGuest *tdx_guest;
 
@@ -151,6 +153,15 @@ static int tdx_kvm_type(X86ConfidentialGuest *cg)
     return KVM_X86_TDX_VM;
 }
 
+static void setup_td_guest_attributes(X86CPU *x86cpu)
+{
+    CPUX86State *env = &x86cpu->env;
+
+    tdx_guest->attributes |= (env->features[FEAT_7_0_ECX] & CPUID_7_0_ECX_PKS) ?
+                             TDX_TD_ATTRIBUTES_PKS : 0;
+    tdx_guest->attributes |= x86cpu->enable_pmu ? TDX_TD_ATTRIBUTES_PERFMON : 0;
+}
+
 static int setup_td_xfam(X86CPU *x86cpu, Error **errp)
 {
     CPUX86State *env = &x86cpu->env;
@@ -214,6 +225,8 @@ int tdx_pre_create_vcpu(CPUState *cpu, Error **errp)
     init_vm = g_malloc0(sizeof(struct kvm_tdx_init_vm) +
                         sizeof(struct kvm_cpuid_entry2) * KVM_MAX_CPUID_ENTRIES);
 
+    setup_td_guest_attributes(x86cpu);
+
     r = setup_td_xfam(x86cpu, errp);
     if (r) {
         return r;