Commit 243d4c02 authored Apr 28, 2016 by Marek Szyprowski Committed by Mauro Carvalho Chehab May 02, 2016

[media] media: exynos4-is: fix deadlock on driver probe



Commit 0c426c47 ("[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>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

parent 89a09566

drivers/media/platform/exynos4-is/media-dev.c

+2 −11

Original line number	Diff line number	Diff line
		@@ -1446,22 +1446,13 @@ static int fimc_md_probe(struct platform_device *pdev)

		platform_set_drvdata(pdev, fmd);

		/* Protect the media graph while we're registering entities */
		mutex_lock(&fmd->media_dev.graph_mutex);

		ret = fimc_md_register_platform_entities(fmd, dev->of_node);
		if (ret) {
		mutex_unlock(&fmd->media_dev.graph_mutex);
		if (ret)
		goto err_clk;
		}

		ret = fimc_md_register_sensor_entities(fmd);
		if (ret) {
		mutex_unlock(&fmd->media_dev.graph_mutex);
		if (ret)
		goto err_m_ent;
		}

		mutex_unlock(&fmd->media_dev.graph_mutex);

		ret = device_create_file(&pdev->dev, &dev_attr_subdev_conf_mode);
		if (ret)