Just mark XFD as always supported for TDX. This simple solution relies
on the fact KVM will report XFD as 0 when it's not supported by the
hardware.
Signed-off-by: Xiaoyao Li <xiaoyao...@intel.com>
Reviewed-by: Zhao Liu <zhao1....@intel.com>
---
target/i386/cpu.h | 1 +
target/i386/kvm/tdx.c | 6 ++++++
2 files changed, 7 insertions(+)
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 132312d70a54..a223e09a25c4 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1126,6 +1126,7 @@ uint64_t x86_cpu_get_supported_feature_word(X86CPU *cpu,
FeatureWord w);
#define CPUID_XSAVE_XSAVEC (1U << 1)
#define CPUID_XSAVE_XGETBV1 (1U << 2)
#define CPUID_XSAVE_XSAVES (1U << 3)
+#define CPUID_XSAVE_XFD (1U << 4)
#define CPUID_6_EAX_ARAT (1U << 2)
diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index df6b71568321..528b5cb4ae47 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -628,6 +628,12 @@ static void tdx_add_supported_cpuid_by_xfam(void)
e->edx |= (tdx_caps->supported_xfam & CPUID_XSTATE_XCR0_MASK) >> 32;
e = find_in_supported_entry(0xd, 1);
+ /*
+ * Mark XFD always support for TDX, it will be cleared finally in
+ * tdx_adjust_cpuid_features() if XFD is unavailable on the hardware
+ * because in this case the original data has it as 0.
+ */
+ e->eax |= CPUID_XSAVE_XFD;
e->ecx |= (tdx_caps->supported_xfam & CPUID_XSTATE_XSS_MASK);
e->edx |= (tdx_caps->supported_xfam & CPUID_XSTATE_XSS_MASK) >> 32;
}
--
2.43.0
