diff --git a/arch/s390/include/asm/string.h b/arch/s390/include/asm/string.h
index 3fae93ddb322..0196fd466a39 100644
--- a/arch/s390/include/asm/string.h
+++ b/arch/s390/include/asm/string.h
@@ -120,7 +120,7 @@ static inline void *memchr(const void * s, int c, size_t n)
 #endif
 
 #ifdef __HAVE_ARCH_MEMSCAN
-static inline void *memscan(void *s, int c, size_t n)
+static inline void *memscan(const void *s, int c, size_t n)
 {
 	const void *ret = s + n;
 
@@ -205,7 +205,7 @@ static inline size_t strnlen(const char * s, size_t n)
 #endif
 #else /* IN_ARCH_STRING_C */
 void *memchr(const void * s, int c, size_t n);
-void *memscan(void *s, int c, size_t n);
+void *memscan(const void *s, int c, size_t n);
 char *strcat(char *dst, const char *src);
 char *strcpy(char *dst, const char *src);
 size_t strlen(const char *s);
diff --git a/arch/s390/lib/string.c b/arch/s390/lib/string.c
index 7d8741818239..ec9786fde1dd 100644
--- a/arch/s390/lib/string.c
+++ b/arch/s390/lib/string.c
@@ -331,7 +331,7 @@ EXPORT_SYMBOL(memcmp);
  * the area if @c is not found
  */
 #ifdef __HAVE_ARCH_MEMSCAN
-void *memscan(void *s, int c, size_t n)
+void *memscan(const void *s, int c, size_t n)
 {
 	const void *ret = s + n;
 
diff --git a/arch/sparc/include/asm/asm-prototypes.h b/arch/sparc/include/asm/asm-prototypes.h
index 4987c735ff56..3a82a86a27a6 100644
--- a/arch/sparc/include/asm/asm-prototypes.h
+++ b/arch/sparc/include/asm/asm-prototypes.h
@@ -13,8 +13,8 @@
 #include <asm/oplib.h>
 #include <linux/atomic.h>
 
-void *__memscan_zero(void *, size_t);
-void *__memscan_generic(void *, int, size_t);
+void *__memscan_zero(const void *, size_t);
+void *__memscan_generic(const void *, int, size_t);
 void *__bzero(void *, size_t);
 void VISenter(void); /* Dummy prototype to supress warning */
 #undef memcpy
diff --git a/arch/sparc/include/asm/string.h b/arch/sparc/include/asm/string.h
index 001a17baf2d5..7761a037b377 100644
--- a/arch/sparc/include/asm/string.h
+++ b/arch/sparc/include/asm/string.h
@@ -21,10 +21,11 @@ void *memmove(void *, const void *, __kernel_size_t);
 
 #define memscan(__arg0, __char, __arg2)						\
 ({										\
-	void *__memscan_zero(void *, size_t);					\
-	void *__memscan_generic(void *, int, size_t);				\
-	void *__retval, *__addr = (__arg0);					\
+	void *__memscan_zero(const void *, size_t);				\
+	void *__memscan_generic(const void *, int, size_t);			\
+	const void *__addr = (__arg0);						\
 	size_t __size = (__arg2);						\
+	void *__retval;								\
 										\
 	if(__builtin_constant_p(__char) && !(__char))				\
 		__retval = __memscan_zero(__addr, __size);			\
diff --git a/arch/x86/include/asm/string_32.h b/arch/x86/include/asm/string_32.h
index 32c0d981a82a..30245f7707e7 100644
--- a/arch/x86/include/asm/string_32.h
+++ b/arch/x86/include/asm/string_32.h
@@ -223,7 +223,7 @@ static inline void *memset32(uint32_t *s, uint32_t v, size_t n)
  * find the first occurrence of byte 'c', or 1 past the area if none
  */
 #define __HAVE_ARCH_MEMSCAN
-extern void *memscan(void *addr, int c, size_t size);
+extern void *memscan(const void *addr, int c, size_t size);
 
 #endif /* __KERNEL__ */
 
diff --git a/arch/x86/lib/string_32.c b/arch/x86/lib/string_32.c
index 53b3f202267c..4124d6678f72 100644
--- a/arch/x86/lib/string_32.c
+++ b/arch/x86/lib/string_32.c
@@ -198,7 +198,7 @@ EXPORT_SYMBOL(memchr);
 #endif
 
 #ifdef __HAVE_ARCH_MEMSCAN
-void *memscan(void *addr, int c, size_t size)
+void *memscan(const void *addr, int c, size_t size)
 {
 	if (!size)
 		return addr;
diff --git a/include/linux/string.h b/include/linux/string.h
index c062c581a98b..a7bff7ed3cb0 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -150,7 +150,7 @@ extern void * memcpy(void *,const void *,__kernel_size_t);
 extern void * memmove(void *,const void *,__kernel_size_t);
 #endif
 #ifndef __HAVE_ARCH_MEMSCAN
-extern void * memscan(void *,int,__kernel_size_t);
+extern void * memscan(const void *,int,__kernel_size_t);
 #endif
 #ifndef __HAVE_ARCH_MEMCMP
 extern int memcmp(const void *,const void *,__kernel_size_t);
diff --git a/lib/string.c b/lib/string.c
index 3d55ef890106..30a63048d4cc 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -725,7 +725,7 @@ EXPORT_SYMBOL(bcmp);
  * returns the address of the first occurrence of @c, or 1 byte past
  * the area if @c is not found
  */
-void *memscan(void *addr, int c, size_t size)
+void *memscan(const void *addr, int c, size_t size)
 {
 	unsigned char *p = addr;
 
