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[PATCH, committed] X86: Don't assert on older Intel CPUs [BZ #20647]
- From: "H.J. Lu" <hongjiu dot lu at intel dot com>
- To: GNU C Library <libc-alpha at sourceware dot org>
- Date: Wed, 12 Oct 2016 08:28:25 -0700
- Subject: [PATCH, committed] X86: Don't assert on older Intel CPUs [BZ #20647]
- Authentication-results: sourceware.org; auth=none
- Reply-to: "H.J. Lu" <hjl dot tools at gmail dot com>
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.
Tested on i686 and x86-64. Checked in.
H.J.
---
[BZ #20647]
* sysdeps/x86/cacheinfo.c (handle_intel): Return -1 if the
maximum CPUID level is less than 2.
---
ChangeLog | 6 ++++++
sysdeps/x86/cacheinfo.c | 4 +++-
2 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/ChangeLog b/ChangeLog
index d129219..81dd89f 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 cf4f64b..35268e8 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. */
--
2.7.4