[PATCH] CMA: correct unlock target

Joonsoo Kim iamjoonsoo.kim at lge.com
Wed May 28 23:29:18 PDT 2014


'cma: Remove potential deadlock situation' introduces per cma area mutex
for bitmap management. It is good, but there is one mistake. When we
can't find appropriate area in bitmap, we release cma_mutex global lock
rather than cma->lock and this is a bug. So fix it.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim at lge.com>

diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index 6f6bffc..83969f8 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -331,7 +331,7 @@ struct page *dma_alloc_from_contiguous(struct device *dev, int count,
 		pageno = bitmap_find_next_zero_area(cma->bitmap, cma->count,
 						    start, count, mask);
 		if (pageno >= cma->count) {
-			mutex_unlock(&cma_mutex);
+			mutex_unlock(&cma->lock);
 			break;
 		}
 		bitmap_set(cma->bitmap, pageno, count);
-- 
1.7.9.5




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