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authorVegard Nossum <vegard.nossum@gmail.com>2008-04-04 02:53:23 +0400
committerVegard Nossum <vegard.nossum@gmail.com>2009-06-15 14:40:02 +0400
commitf85612967c93b67b10dd240e3e8bf8a0eee9def7 (patch)
tree184a70bc888b35235ee0b1805a06f90fd45295d8 /arch/x86/include/asm/string_32.h
parentf8b4ece2a94693b7d2dd32ea716cb92545b5dce6 (diff)
downloadlinux-f85612967c93b67b10dd240e3e8bf8a0eee9def7.tar.xz
x86: add hooks for kmemcheck
The hooks that we modify are: - Page fault handler (to handle kmemcheck faults) - Debug exception handler (to hide pages after single-stepping the instruction that caused the page fault) Also redefine memset() to use the optimized version if kmemcheck is enabled. (Thanks to Pekka Enberg for minimizing the impact on the page fault handler.) As kmemcheck doesn't handle MMX/SSE instructions (yet), we also disable the optimized xor code, and rely instead on the generic C implementation in order to avoid false-positive warnings. Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no> [whitespace fixlet] Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
Diffstat (limited to 'arch/x86/include/asm/string_32.h')
-rw-r--r--arch/x86/include/asm/string_32.h8
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/x86/include/asm/string_32.h b/arch/x86/include/asm/string_32.h
index 0e0e3ba827f7..c86f452256de 100644
--- a/arch/x86/include/asm/string_32.h
+++ b/arch/x86/include/asm/string_32.h
@@ -177,10 +177,18 @@ static inline void *__memcpy3d(void *to, const void *from, size_t len)
* No 3D Now!
*/
+#ifndef CONFIG_KMEMCHECK
#define memcpy(t, f, n) \
(__builtin_constant_p((n)) \
? __constant_memcpy((t), (f), (n)) \
: __memcpy((t), (f), (n)))
+#else
+/*
+ * kmemcheck becomes very happy if we use the REP instructions unconditionally,
+ * because it means that we know both memory operands in advance.
+ */
+#define memcpy(t, f, n) __memcpy((t), (f), (n))
+#endif
#endif