[2/2] media: s3c-camif: fix deadlock on driver probe()

Message ID 1461839104-29135-2-git-send-email-m.szyprowski@samsung.com
State New
Headers show

Commit Message

Marek Szyprowski April 28, 2016, 10:25 a.m.
Commit 0c426c472b5585ed6e59160359c979506d45ae49 ("[media] media: Always
keep a graph walk large enough around") changed
media_device_register_entity() function to take mdev->graph_mutex. This
causes deadlock in driver probe, which calls (indirectly) this function
with ->graph_mutex taken. This patch removes taking ->graph_mutex in
driver probe to avoid deadlock. Other drivers don't take ->graph_mutex
for entity registration, so this change should be safe.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

---
 drivers/media/platform/s3c-camif/camif-core.c | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

-- 
1.9.2

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Patch

diff --git a/drivers/media/platform/s3c-camif/camif-core.c b/drivers/media/platform/s3c-camif/camif-core.c
index 0b44b9accf50..af237af204e2 100644
--- a/drivers/media/platform/s3c-camif/camif-core.c
+++ b/drivers/media/platform/s3c-camif/camif-core.c
@@ -493,21 +493,17 @@  static int s3c_camif_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto err_sens;
 
-	mutex_lock(&camif->media_dev.graph_mutex);
-
 	ret = v4l2_device_register_subdev_nodes(&camif->v4l2_dev);
 	if (ret < 0)
-		goto err_unlock;
+		goto err_sens;
 
 	ret = camif_register_video_nodes(camif);
 	if (ret < 0)
-		goto err_unlock;
+		goto err_sens;
 
 	ret = camif_create_media_links(camif);
 	if (ret < 0)
-		goto err_unlock;
-
-	mutex_unlock(&camif->media_dev.graph_mutex);
+		goto err_sens;
 
 	ret = media_device_register(&camif->media_dev);
 	if (ret < 0)
@@ -516,8 +512,6 @@  static int s3c_camif_probe(struct platform_device *pdev)
 	pm_runtime_put(dev);
 	return 0;
 
-err_unlock:
-	mutex_unlock(&camif->media_dev.graph_mutex);
 err_sens:
 	v4l2_device_unregister(&camif->v4l2_dev);
 	media_device_unregister(&camif->media_dev);