[PATCH RFC 1/7] kvm: x86: Expose XFD CPUID to guest

From: Jing Liu
Date: Sun Feb 07 2021 - 01:58:48 EST


Intel's Extended Feature Disable (XFD) feature is an extension
to the XSAVE feature that allows an operating system to enable
a feature while preventing specific user threads from using
the feature. A processor that supports XFD enumerates
CPUID.(EAX=0DH,ECX=1):EAX[4] as 1.

Signed-off-by: Jing Liu <jing2.liu@xxxxxxxxxxxxxxx>
---
arch/x86/kvm/cpuid.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 83637a2ff605..04a73c395c71 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -437,7 +437,7 @@ void kvm_set_cpu_caps(void)
);

kvm_cpu_cap_mask(CPUID_D_1_EAX,
- F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | F(XSAVES)
+ F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | F(XSAVES) | F(XFD)
);

kvm_cpu_cap_mask(CPUID_8000_0001_ECX,
--
2.18.4