SLUB: CONFIG_LARGE_ALLOCS must consider MAX_ORDER limit

Take MAX_ORDER into consideration when determining KMALLOC_SHIFT_HIGH.
Otherwise we may run into a situation where we attempt to create general
slabs larger than MAX_ORDER.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index ea27065..fd6627e 100644 (file)
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -60,7 +60,8 @@ struct kmem_cache {
 #define KMALLOC_SHIFT_LOW 3
 
 #ifdef CONFIG_LARGE_ALLOCS
-#define KMALLOC_SHIFT_HIGH 25
+#define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT) =< 25 ? \
+                               (MAX_ORDER + PAGE_SHIFT - 1) : 25)
 #else
 #if !defined(CONFIG_MMU) || NR_CPUS > 512 || MAX_NUMNODES > 256
 #define KMALLOC_SHIFT_HIGH 20
@@ -87,6 +88,9 @@ static inline int kmalloc_index(int size)
         */
        WARN_ON_ONCE(size == 0);
 
+       if (size >= (1 << KMALLOC_SHIFT_HIGH))
+               return -1;
+
        if (size > 64 && size <= 96)
                return 1;
        if (size > 128 && size <= 192)