1 files changed, 31 insertions, 23 deletions

diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
index b8576fd6bd0e..7254c20007f8 100644
--- a/drivers/dma/dmatest.c
+++ b/drivers/dma/dmatest.c
@@ -148,6 +148,12 @@ MODULE_PARM_DESC(run, "Run the test (default: false)");
 #define PATTERN_OVERWRITE	0x20
 #define PATTERN_COUNT_MASK	0x1f
 
+/* poor man's completion - we want to use wait_event_freezable() on it */
+struct dmatest_done {
+	bool			done;
+	wait_queue_head_t	*wait;
+};
+
 struct dmatest_thread {
 	struct list_head	node;
 	struct dmatest_info	*info;
@@ -156,6 +162,8 @@ struct dmatest_thread {
 	u8			**srcs;
 	u8			**dsts;
 	enum dma_transaction_type type;
+	wait_queue_head_t done_wait;
+	struct dmatest_done test_done;
 	bool			done;
 };
 
@@ -316,18 +324,25 @@ static unsigned int dmatest_verify(u8 **bufs, unsigned int start,
 	return error_count;
 }
 
-/* poor man's completion - we want to use wait_event_freezable() on it */
-struct dmatest_done {
-	bool			done;
-	wait_queue_head_t	*wait;
-};
 
 static void dmatest_callback(void *arg)
 {
 	struct dmatest_done *done = arg;
-
-	done->done = true;
-	wake_up_all(done->wait);
+	struct dmatest_thread *thread =
+		container_of(arg, struct dmatest_thread, done_wait);
+	if (!thread->done) {
+		done->done = true;
+		wake_up_all(done->wait);
+	} else {
+		/*
+		 * If thread->done, it means that this callback occurred
+		 * after the parent thread has cleaned up. This can
+		 * happen in the case that driver doesn't implement
+		 * the terminate_all() functionality and a dma operation
+		 * did not occur within the timeout period
+		 */
+		WARN(1, "dmatest: Kernel memory may be corrupted!!\n");
+	}
 }
 
 static unsigned int min_odd(unsigned int x, unsigned int y)
@@ -398,9 +413,8 @@ static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)
  */
 static int dmatest_func(void *data)
 {
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(done_wait);
 	struct dmatest_thread	*thread = data;
-	struct dmatest_done	done = { .wait = &done_wait };
+	struct dmatest_done	*done = &thread->test_done;
 	struct dmatest_info	*info;
 	struct dmatest_params	*params;
 	struct dma_chan		*chan;
@@ -605,9 +619,9 @@ static int dmatest_func(void *data)
 			continue;
 		}
 
-		done.done = false;
+		done->done = false;
 		tx->callback = dmatest_callback;
-		tx->callback_param = &done;
+		tx->callback_param = done;
 		cookie = tx->tx_submit(tx);
 
 		if (dma_submit_error(cookie)) {
@@ -620,20 +634,12 @@ static int dmatest_func(void *data)
 		}
 		dma_async_issue_pending(chan);
 
-		wait_event_freezable_timeout(done_wait, done.done,
+		wait_event_freezable_timeout(thread->done_wait, done->done,
 					     msecs_to_jiffies(params->timeout));
 
 		status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
 
-		if (!done.done) {
-			/*
-			 * We're leaving the timed out dma operation with
-			 * dangling pointer to done_wait.  To make this
-			 * correct, we'll need to allocate wait_done for
-			 * each test iteration and perform "who's gonna
-			 * free it this time?" dancing.  For now, just
-			 * leave it dangling.
-			 */
+		if (!done->done) {
 			dmaengine_unmap_put(um);
 			result("test timed out", total_tests, src_off, dst_off,
 			       len, 0);
@@ -707,7 +713,7 @@ err_thread_type:
 		dmatest_KBs(runtime, total_len), ret);
 
 	/* terminate all transfers on specified channels */
-	if (ret)
+	if (ret || failed_tests)
 		dmaengine_terminate_all(chan);
 
 	thread->done = true;
@@ -765,6 +771,8 @@ static int dmatest_add_threads(struct dmatest_info *info,
 		thread->info = info;
 		thread->chan = dtc->chan;
 		thread->type = type;
+		thread->test_done.wait = &thread->done_wait;
+		init_waitqueue_head(&thread->done_wait);
 		smp_wmb();
 		thread->task = kthread_create(dmatest_func, thread, "%s-%s%u",
 				dma_chan_name(chan), op, i);