Commit a5c96d8a authored Jul 19, 2007 by Linus Torvalds

Fix up non-NUMA SLAB configuration for zero-sized allocations



I suspect Christoph tested his code only in the NUMA configuration, for
the combination of SLAB+non-NUMA the zero-sized kmalloc's would not work.

Of course, this would only trigger in configurations where those zero-
sized allocations happen (not very common), so that may explain why it
wasn't more widely noticed.

Seen by by Andi Kleen under qemu, and there seems to be a report by
Michael Tsirkin on it too.

Cc: Andi Kleen <ak@suse.de>
Cc: Roland Dreier <rdreier@cisco.com>
Cc: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent ce8c2293

mm/slab.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -3690,8 +3690,8 @@ static __always_inline void *__do_kmalloc(size_t size, gfp_t flags,
		* functions.
		*/
		cachep = __find_general_cachep(size, flags);
		if (unlikely(cachep == NULL))
		return NULL;
		if (unlikely(ZERO_OR_NULL_PTR(cachep)))
		return cachep;
		return __cache_alloc(cachep, flags, caller);
		}