[PATCH v6 12/60] i386/tdx: Wire CPU features up with attributes of TD guest

Xiaoyao Li
2024-11-05T06:37:12Z

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>
---
target/i386/kvm/tdx.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index e8fd5c7d49e7..6cf81f788fe0 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -21,6 +21,8 @@
#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;

@@ -139,6 +141,15 @@ 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;
@@ -200,6 +211,8 @@ 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;
--
2.34.1