arch: personality independent stack top

New arch macro STACK_TOP_MAX it gives the larges valid stack address for the
architecture in question.

It differs from STACK_TOP in that it will not distinguish between
personalities but will always return the largest possible address.

This is used to create the initial stack on execve, which we will move down to
the proper location once the binfmt code has figured out where that is.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ollie Wild <aaw@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/asm-alpha/a.out.h

@@ -101,6 +101,8 @@ struct exec
 #define STACK_TOP \
   (current->personality & ADDR_LIMIT_32BIT ? 0x80000000 : 0x00120000000UL)
 
+#define STACK_TOP_MAX	0x00120000000UL
+
 #endif
 
 #endif /* __A_OUT_GNU_H__ */

include/asm-arm/a.out.h

@@ -30,6 +30,7 @@ struct exec
 #ifdef __KERNEL__
 #define STACK_TOP	((current->personality == PER_LINUX_32BIT) ? \
 			 TASK_SIZE : TASK_SIZE_26)
+#define STACK_TOP_MAX	TASK_SIZE
 #endif
 
 #ifndef LIBRARY_START_TEXT

include/asm-arm26/a.out.h

@@ -29,6 +29,7 @@ struct exec
 
 #ifdef __KERNEL__
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 #endif
 
 #ifndef LIBRARY_START_TEXT

include/asm-avr32/a.out.h

@@ -20,6 +20,7 @@ struct exec
 #ifdef __KERNEL__
 
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 
 #endif
 

include/asm-cris/a.out.h

@@ -8,6 +8,7 @@
 
 /* grabbed from the intel stuff  */   
 #define STACK_TOP TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 
 
 struct exec

include/asm-frv/mem-layout.h

@@ -60,6 +60,7 @@
  */
 #define BRK_BASE			__UL(2 * 1024 * 1024 + PAGE_SIZE)
 #define STACK_TOP			__UL(2 * 1024 * 1024)
+#define STACK_TOP_MAX	STACK_TOP
 
 /* userspace process size */
 #ifdef CONFIG_MMU

include/asm-h8300/a.out.h

@@ -20,6 +20,7 @@ struct exec
 #ifdef __KERNEL__
 
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 
 #endif
 

include/asm-i386/a.out.h

@@ -20,6 +20,7 @@ struct exec
 #ifdef __KERNEL__
 
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 
 #endif
 

include/asm-ia64/ustack.h

@@ -11,6 +11,7 @@
 /* The absolute hard limit for stack size is 1/2 of the mappable space in the region */
 #define MAX_USER_STACK_SIZE	(RGN_MAP_LIMIT/2)
 #define STACK_TOP		(0x6000000000000000UL + RGN_MAP_LIMIT)
+#define STACK_TOP_MAX		STACK_TOP
 #endif
 
 /* Make a default stack size of 2GiB */

include/asm-m32r/a.out.h

@@ -20,6 +20,7 @@ struct exec
 #ifdef __KERNEL__
 
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 
 #endif
 

include/asm-m68k/a.out.h

@@ -20,6 +20,7 @@ struct exec
 #ifdef __KERNEL__
 
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 
 #endif
 

include/asm-mips/a.out.h

@@ -40,6 +40,7 @@ struct exec
 #ifdef CONFIG_64BIT
 #define STACK_TOP	(current->thread.mflags & MF_32BIT_ADDR ? TASK_SIZE32 : TASK_SIZE)
 #endif
+#define STACK_TOP_MAX	TASK_SIZE
 
 #endif
 

include/asm-parisc/a.out.h

@@ -23,6 +23,7 @@ struct exec
  * prumpf */
 
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	DEFAULT_TASK_SIZE
 
 #endif
 

include/asm-powerpc/a.out.h

@@ -26,9 +26,12 @@ struct exec
 #define STACK_TOP (test_thread_flag(TIF_32BIT) ? \
 		   STACK_TOP_USER32 : STACK_TOP_USER64)
 
+#define STACK_TOP_MAX STACK_TOP_USER64
+
 #else /* __powerpc64__ */
 
 #define STACK_TOP TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 
 #endif /* __powerpc64__ */
 #endif /* __KERNEL__ */

include/asm-s390/a.out.h

@@ -32,6 +32,7 @@ struct exec
 #ifdef __KERNEL__
 
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	DEFAULT_TASK_SIZE
 
 #endif
 

include/asm-sh/a.out.h

@@ -20,6 +20,7 @@ struct exec
 #ifdef __KERNEL__
 
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 
 #endif
 

include/asm-sh64/a.out.h

@@ -31,6 +31,7 @@ struct exec
 #ifdef __KERNEL__
 
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 
 #endif
 

include/asm-sparc/a.out.h

@@ -92,6 +92,7 @@ struct relocation_info /* used when header.a_machtype == M_SPARC */
 #include <asm/page.h>
 
 #define STACK_TOP	(PAGE_OFFSET - PAGE_SIZE)
+#define STACK_TOP_MAX	STACK_TOP
 
 #endif /* __KERNEL__ */
 

include/asm-sparc64/a.out.h

@@ -101,6 +101,8 @@ struct relocation_info /* used when header.a_machtype == M_SPARC */
 #define STACK_TOP (test_thread_flag(TIF_32BIT) ? \
 		   STACK_TOP32 : STACK_TOP64)
 
+#define STACK_TOP_MAX STACK_TOP64
+
 #endif
 
 #endif /* !(__ASSEMBLY__) */

include/asm-um/a.out.h

@@ -17,4 +17,6 @@ extern int honeypot;
 #define STACK_TOP \
 	CHOOSE_MODE((honeypot ? host_task_size : task_size), task_size)
 
+#define STACK_TOP_MAX	STACK_TOP
+
 #endif

include/asm-x86_64/a.out.h

@@ -21,7 +21,8 @@ struct exec
 
 #ifdef __KERNEL__
 #include <linux/thread_info.h>
-#define STACK_TOP TASK_SIZE
+#define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	TASK_SIZE64
 #endif
 
 #endif /* __A_OUT_GNU_H__ */

include/asm-xtensa/a.out.h

@@ -17,6 +17,7 @@
 /* Note: the kernel needs the a.out definitions, even if only ELF is used. */
 
 #define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
 
 struct exec
 {