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authorDavid Woodhouse <dwmw2@infradead.org>2013-01-28 17:49:50 +0000
committerH. Peter Anvin <hpa@linux.intel.com>2013-01-28 16:59:55 -0800
commit2b9b6d8c715b23fa119261c32ad360681f4464a9 (patch)
treec26f79a3e138b5739e1a1f6b95c0ef58b64c2949 /arch
parent83a57a4de1a222c351667ef9a0fedaac1295e85b (diff)
x86: Require MOVBE feature in cpuid when we use it
Add MOVBE to asm/required-features.h so we check for it during startup and don't bother checking for it later. CONFIG_MATOM is used because it corresponds to -march=atom in the Makefiles. If the rules get more complicated it may be necessary to make this an explicit Kconfig option which uses -mmovbe/-mno-movbe to control the use of this instruction explicitly. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Link: http://lkml.kernel.org/r/1359395390.3529.65.camel@shinybook.infradead.org [ hpa: added a patch description ] Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/include/asm/required-features.h8
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/x86/include/asm/required-features.h b/arch/x86/include/asm/required-features.h
index 6c7fc25f2c34..5c6e4fb370f5 100644
--- a/arch/x86/include/asm/required-features.h
+++ b/arch/x86/include/asm/required-features.h
@@ -47,6 +47,12 @@
# define NEED_NOPL 0
#endif
+#ifdef CONFIG_MATOM
+# define NEED_MOVBE (1<<(X86_FEATURE_MOVBE & 31))
+#else
+# define NEED_MOVBE 0
+#endif
+
#ifdef CONFIG_X86_64
#ifdef CONFIG_PARAVIRT
/* Paravirtualized systems may not have PSE or PGE available */
@@ -80,7 +86,7 @@
#define REQUIRED_MASK2 0
#define REQUIRED_MASK3 (NEED_NOPL)
-#define REQUIRED_MASK4 0
+#define REQUIRED_MASK4 (NEED_MOVBE)
#define REQUIRED_MASK5 0
#define REQUIRED_MASK6 0
#define REQUIRED_MASK7 0