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, 7 insertions, 3 deletions

diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index c38083871f11..2defd1308b04 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -463,7 +463,7 @@ static int active_pfn_set_overlap(unsigned long pfn, int overlap)
 	int i;
 
 	if (overlap > ACTIVE_PFN_MAX_OVERLAP || overlap < 0)
-		return 0;
+		return overlap;
 
 	for (i = RADIX_TREE_MAX_TAGS - 1; i >= 0; i--)
 		if (overlap & 1 << i)
@@ -486,7 +486,7 @@ static void active_pfn_inc_overlap(unsigned long pfn)
 	 * debug_dma_assert_idle() as the pfn may be marked idle
 	 * prematurely.
 	 */
-	WARN_ONCE(overlap == 0,
+	WARN_ONCE(overlap > ACTIVE_PFN_MAX_OVERLAP,
 		  "DMA-API: exceeded %d overlapping mappings of pfn %lx\n",
 		  ACTIVE_PFN_MAX_OVERLAP, pfn);
 }
@@ -517,7 +517,11 @@ static void active_pfn_remove(struct dma_debug_entry *entry)
 	unsigned long flags;
 
 	spin_lock_irqsave(&radix_lock, flags);
-	if (active_pfn_dec_overlap(entry->pfn) == 0)
+	/* since we are counting overlaps the final put of the
+	 * entry->pfn will occur when the overlap count is 0.
+	 * active_pfn_dec_overlap() returns -1 in that case
+	 */
+	if (active_pfn_dec_overlap(entry->pfn) < 0)
 		radix_tree_delete(&dma_active_pfn, entry->pfn);
 	spin_unlock_irqrestore(&radix_lock, flags);
 }