x86, xsave: struct _fpstate extensions to include extended state information

Bytes 464..511 in the current 512byte layout of fxsave/fxrstor
frame, are reserved for SW usage. On cpu's supporting xsave/xrstor, these bytes
are used to extended the fpstate pointer in the sigcontext, which now includes
the extended state information along with fpstate information.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 5 insertions, 1 deletions

diff --git a/include/asm-x86/sigcontext32.h b/include/asm-x86/sigcontext32.h
index 4e2ec732dd01..8c347032c2f2 100644
--- a/include/asm-x86/sigcontext32.h
+++ b/include/asm-x86/sigcontext32.h
@@ -40,7 +40,11 @@ struct _fpstate_ia32 {
         __u32   reserved;
         struct _fpxreg  _fxsr_st[8];
         struct _xmmreg  _xmm[8];        /* It's actually 16 */
-        __u32   padding[56];
+        __u32   padding[44];
+        union {
+                __u32 padding2[12];
+                struct _fpx_sw_bytes sw_reserved;
+        };
 };
 
 struct sigcontext_ia32 {