[PATCH v2 4/8] x86: Add XFD faulting bit for state components

[Yang Zhong]

From: Jing Liu <jing2.liu@intel.com>

Intel introduces XFD faulting mechanism for extended
XSAVE features to dynamically enable the features in
runtime. If CPUID (EAX=0Dh, ECX=n, n>1).ECX[2] is set
as 1, it indicates support for XFD faulting of this
state component.

Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
---
 target/i386/cpu.h | 2 ++
 target/i386/cpu.c | 3 ++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index d4ad0f56bd..f7fc2e97a6 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -558,8 +558,10 @@ typedef enum X86Seg {
 #define ARCH_REQ_XCOMP_GUEST_PERM       0x1025
 
 #define ESA_FEATURE_ALIGN64_BIT         1
+#define ESA_FEATURE_XFD_BIT             2
 
 #define ESA_FEATURE_ALIGN64_MASK        (1U << ESA_FEATURE_ALIGN64_BIT)
+#define ESA_FEATURE_XFD_MASK            (1U << ESA_FEATURE_XFD_BIT)
 
 
 /* CPUID feature words */
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 377d993438..5a7ee8c7e1 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -5497,7 +5497,8 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, 
uint32_t count,
                 const ExtSaveArea *esa = &x86_ext_save_areas[count];
                 *eax = esa->size;
                 *ebx = esa->offset;
-                *ecx = esa->ecx & ESA_FEATURE_ALIGN64_MASK;
+                *ecx = (esa->ecx & ESA_FEATURE_ALIGN64_MASK) |
+                       (esa->ecx & ESA_FEATURE_XFD_MASK);
             }
         }
         break;