[RFC PATCH v4 12/36] i386/tdx: Wire CPU features up with attributes of TD guest

[Xiaoyao Li]

For QEMU VMs, PKS is configured via CPUID_7_0_ECX_PKS and PMU is
configured by x86cpu->enable_pmu. Reuse the existing configuration
interface for TDX VMs.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
---
 target/i386/kvm/tdx.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index 3472b59c2dbb..e9c6e6fb396c 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -31,6 +31,9 @@
                                      (1ULL << KVM_FEATURE_PV_SCHED_YIELD) | \
                                      (1ULL << KVM_FEATURE_MSI_EXT_DEST_ID))
 
+#define TDX_TD_ATTRIBUTES_PKS               BIT_ULL(30)
+#define TDX_TD_ATTRIBUTES_PERFMON           BIT_ULL(63)
+
 static TdxGuest *tdx_guest;
 
 /* It's valid after kvm_confidential_guest_init()->kvm_tdx_init() */
@@ -166,6 +169,15 @@ void tdx_get_supported_cpuid(uint32_t function, uint32_t 
index, int reg,
     }
 }
 
+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;
+}
+
 int tdx_pre_create_vcpu(CPUState *cpu)
 {
     MachineState *ms = MACHINE(qdev_get_machine());
@@ -179,6 +191,8 @@ int tdx_pre_create_vcpu(CPUState *cpu)
         goto out;
     }
 
+    setup_td_guest_attributes(x86cpu);
+
     memset(&init_vm, 0, sizeof(init_vm));
     init_vm.cpuid.nent = kvm_x86_arch_cpuid(env, init_vm.entries, 0);
 
-- 
2.27.0