Merge branch 'akpm' (patches from Andrew Morton)

Merge random fixes from Andrew Morton:
 "Random fixes.

  I have one batch remaining for -rc1, mainly zram changes which await a
  merge of Jens's trees"

* emailed patches fron Andrew Morton akpm@linux-foundation.org>:
  MAINTAINERS: ADI Linux development mailing lists: change to the new server
  Documentation: fix multiple typo occurences s/KenelVersion/KernelVersion/
  dma-debug: fix overlap detection
  memblock: add limit checking to memblock_virt_alloc
  mm/readahead.c: fix do_readahead() for no readpage(s)
  mm/slub.c: do not VM_BUG_ON_PAGE() for temporary on-stack pages
  slab: fix wrong retval on kmem_cache_create_memcg error path
  s390/compat: change parameter types from unsigned long to compat_ulong_t
  fs/compat: fix lookup_dcookie() parameter handling
  fs/compat: fix parameter handling for compat readv/writev syscalls
  mm/mempolicy.c: convert to pr_foo()
  mm: numa: initialise numa balancing after jump label initialisation
  mm/page-writeback.c: do not count anon pages as dirtyable memory
  mm/page-writeback.c: fix dirty_balance_reserve subtraction from dirtyable memory
  mm: document improved handling of swappiness==0
  lib/genalloc.c: add check gen_pool_dma_alloc() if dma pointer is not NULL

1 files changed, 3 insertions, 2 deletions

diff --git a/lib/genalloc.c b/lib/genalloc.c
index dda31168844f..bdb9a456bcbb 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -316,7 +316,7 @@ EXPORT_SYMBOL(gen_pool_alloc);
  * gen_pool_dma_alloc - allocate special memory from the pool for DMA usage
  * @pool: pool to allocate from
  * @size: number of bytes to allocate from the pool
- * @dma: dma-view physical address
+ * @dma: dma-view physical address return value.  Use NULL if unneeded.
  *
  * Allocate the requested number of bytes from the specified pool.
  * Uses the pool allocation function (with first-fit algorithm by default).
@@ -334,7 +334,8 @@ void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
 	if (!vaddr)
 		return NULL;
 
-	*dma = gen_pool_virt_to_phys(pool, vaddr);
+	if (dma)
+		*dma = gen_pool_virt_to_phys(pool, vaddr);
 
 	return (void *)vaddr;
 }