mm/memblock.c: avoid abuse of RED_INACTIVE

RED_INACTIVE is a slab thing, and reusing it for memblock was
inappropriate, because memblock is dealing with phys_addr_t's which have a
Kconfigurable sizeof().

Create a new poison type for this application.  Fixes the sparse warning

    warning: cast truncates bits from constant value (9f911029d74e35b becomes 9d74e35b)

Reported-by: H Hartley Sweeten <[email protected]>
Tested-by: H Hartley Sweeten <[email protected]>
Acked-by: Pekka Enberg <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

include/linux/poison.h

@@ -40,6 +40,12 @@
 #define	RED_INACTIVE	0x09F911029D74E35BULL	/* when obj is inactive */
 #define	RED_ACTIVE	0xD84156C5635688C0ULL	/* when obj is active */
 
+#ifdef CONFIG_PHYS_ADDR_T_64BIT
+#define MEMBLOCK_INACTIVE	0x3a84fb0144c9e71bULL
+#else
+#define MEMBLOCK_INACTIVE	0x44c9e71bUL
+#endif
+
 #define SLUB_RED_INACTIVE	0xbb
 #define SLUB_RED_ACTIVE		0xcc
 

mm/memblock.c

@@ -758,9 +758,9 @@ void __init memblock_analyze(void)
 
 	/* Check marker in the unused last array entry */
 	WARN_ON(memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS].base
-		!= (phys_addr_t)RED_INACTIVE);
+		!= MEMBLOCK_INACTIVE);
 	WARN_ON(memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS].base
-		!= (phys_addr_t)RED_INACTIVE);
+		!= MEMBLOCK_INACTIVE);
 
 	memblock.memory_size = 0;
 
@@ -786,8 +786,8 @@ void __init memblock_init(void)
 	memblock.reserved.max	= INIT_MEMBLOCK_REGIONS;
 
 	/* Write a marker in the unused last array entry */
-	memblock.memory.regions[INIT_MEMBLOCK_REGIONS].base = (phys_addr_t)RED_INACTIVE;
-	memblock.reserved.regions[INIT_MEMBLOCK_REGIONS].base = (phys_addr_t)RED_INACTIVE;
+	memblock.memory.regions[INIT_MEMBLOCK_REGIONS].base = MEMBLOCK_INACTIVE;
+	memblock.reserved.regions[INIT_MEMBLOCK_REGIONS].base = MEMBLOCK_INACTIVE;
 
 	/* Create a dummy zero size MEMBLOCK which will get coalesced away later.
 	 * This simplifies the memblock_add() code below...