From: H.J. Lu <hjl.tools@gmail.com>
Date: Wed, 12 Oct 2016 15:22:52 +0000 (-0700)
Subject: X86: Don't assert on older Intel CPUs [BZ #20647]
X-Git-Tag: glibc-2.25~410
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6a824767d8948faf10d8d3a602eb4f2a59431601;p=thirdparty%2Fglibc.git

X86: Don't assert on older Intel CPUs [BZ #20647]

Since the maximum CPUID level of older Intel CPUs is 1, change
handle_intel to return -1, instead of assert, when the maximum
CPUID level is less than 2.

	[BZ #20647]
	* sysdeps/x86/cacheinfo.c (handle_intel): Return -1 if the
	maximum CPUID level is less than 2.
---

diff --git a/ChangeLog b/ChangeLog
index d129219fd17..81dd89ff27c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2016-10-12  H.J. Lu  <hongjiu.lu@intel.com>
+
+	[BZ #20647]
+	* sysdeps/x86/cacheinfo.c (handle_intel): Return -1 if the
+	maximum CPUID level is less than 2.
+
 2016-10-12  Joseph Myers  <joseph@codesourcery.com>
 
 	* math/bits/mathcalls.h [__GLIBC_USE (IEC_60559_BFP_EXT)]
diff --git a/sysdeps/x86/cacheinfo.c b/sysdeps/x86/cacheinfo.c
index cf4f64b0d8e..35268e8d9af 100644
--- a/sysdeps/x86/cacheinfo.c
+++ b/sysdeps/x86/cacheinfo.c
@@ -259,7 +259,9 @@ intel_check_word (int name, unsigned int value, bool *has_level_2,
 static long int __attribute__ ((noinline))
 handle_intel (int name, unsigned int maxidx)
 {
-  assert (maxidx >= 2);
+  /* Return -1 for older CPUs.  */
+  if (maxidx < 2)
+    return -1;
 
   /* OK, we can use the CPUID instruction to get all info about the
      caches.  */