Fix check for AVX enablement

The AVX bit is set if the CPU supports AVX.  But this doesn't mean the
kernel does.  Add checks according to Intel's documentation.

1 files changed, 18 insertions, 4 deletions

diff --git a/elf/tst-audit6.c b/elf/tst-audit6.c
index 1f6dcb16e9..64209a152e 100644
--- a/elf/tst-audit6.c
+++ b/elf/tst-audit6.c
@@ -8,14 +8,28 @@
 extern __m128i audit_test (__m128i, __m128i, __m128i, __m128i,
 			   __m128i, __m128i, __m128i, __m128i);
 
-int
-main (void)
+
+static int
+avx_enabled (void)
 {
   unsigned int eax, ebx, ecx, edx;
 
+  if (__get_cpuid (1, &eax, &ebx, &ecx, &edx) == 0
+      || (ecx & (bit_AVX | bit_OSXSAVE)) != (bit_AVX | bit_OSXSAVE))
+    return 0;
+
+  /* Check the OS has AVX and SSE saving enabled.  */
+  asm ("xgetbv" : "=a" (eax), "=d" (edx) : "c" (0));
+
+  return (eax & 6) == 6;
+}
+
+
+int
+main (void)
+{
   /* Run AVX test only if AVX is supported.  */
-  if (__get_cpuid (1, &eax, &ebx, &ecx, &edx)
-      && (ecx & bit_AVX))
+  if (avx_enabled ())
     {
       __m128i xmm = _mm_setzero_si128 ();
       __m128i ret = audit_test (xmm, xmm, xmm, xmm, xmm, xmm, xmm, xmm);