Protect the fimc/fimc-lite video nodes unregistration with their video
lock. This prevents a kernel crash when e.g. udev opens a video node
right after the driver registers it and then the driver tries to
unregister it and defers its probing. Using video_is_unregistered()
together with the video mutex allows safe unregistration of the video
nodes at any time.
Signed-off-by: Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx>
Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
---
drivers/media/platform/exynos4-is/fimc-capture.c | 4 ++++
drivers/media/platform/exynos4-is/fimc-lite.c | 4 ++++
2 files changed, 8 insertions(+)
diff --git a/drivers/media/platform/exynos4-is/fimc-capture.c b/drivers/media/platform/exynos4-is/fimc-capture.c
index c2586a2..25f8a1e 100644
--- a/drivers/media/platform/exynos4-is/fimc-capture.c
+++ b/drivers/media/platform/exynos4-is/fimc-capture.c
@@ -1855,6 +1855,8 @@ static void fimc_capture_subdev_unregistered(struct v4l2_subdev *sd)
if (fimc == NULL)
return;
+ mutex_lock(&fimc->lock);
+
fimc_unregister_m2m_device(fimc);
vdev = &fimc->vid_cap.ve.vdev;
@@ -1866,6 +1868,8 @@ static void fimc_capture_subdev_unregistered(struct v4l2_subdev *sd)
}
kfree(fimc->vid_cap.ctx);
fimc->vid_cap.ctx = NULL;
+
+ mutex_unlock(&fimc->lock);
}
static const struct v4l2_subdev_internal_ops fimc_capture_sd_internal_ops = {
diff --git a/drivers/media/platform/exynos4-is/fimc-lite.c b/drivers/media/platform/exynos4-is/fimc-lite.c
index 27232cd..142788a 100644
--- a/drivers/media/platform/exynos4-is/fimc-lite.c
+++ b/drivers/media/platform/exynos4-is/fimc-lite.c
@@ -1300,11 +1300,15 @@ static void fimc_lite_subdev_unregistered(struct v4l2_subdev *sd)
if (fimc == NULL)
return;
+ mutex_lock(&fimc->lock);
+
if (video_is_registered(&fimc->ve.vdev)) {
video_unregister_device(&fimc->ve.vdev);
media_entity_cleanup(&fimc->ve.vdev.entity);
fimc->ve.pipe = NULL;
}
+
+ mutex_unlock(&fimc->lock);
}
static const struct v4l2_subdev_internal_ops fimc_lite_subdev_internal_ops = {
--
1.7.9.5
--
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