Fix unbalanced mutex in dma_pool_create().

commit 153a9f131f50420b7ce008c94f1c6374cbc460d7 upstream.

dma_pool_create() needs to unlock the mutex in error case.  The bug was
introduced in the 3.16 by commit cc6b664aa26d ("mm/dmapool.c: remove
redundant NULL check for dev in dma_pool_create()")/

Signed-off-by: Krzysztof Hałasa <khc@piap.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/mm/dmapool.c b/mm/dmapool.c
index 306baa594f95cd8ed8e5c945e4cc46e4f19c1f93..ba8019b063e18ecb14da4cf3a64dfa671586f8e0 100644 (file)
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -176,7 +176,7 @@ struct dma_pool *dma_pool_create(const char *name, struct device *dev,
        if (list_empty(&dev->dma_pools) &&
            device_create_file(dev, &dev_attr_pools)) {
                kfree(retval);
-               return NULL;
+               retval = NULL;
        } else
                list_add(&retval->pools, &dev->dma_pools);
        mutex_unlock(&pools_lock);