It is not possible to use devm_kzalloc since that memory is
freed immediately when the device instance is unbound.
Various objects like the video device may still be in use
since someone has the device node open, and when that is closed
it expects the memory to be around.
So use kzalloc and release it at the appropriate time.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
---
drivers/media/platform/vim2m.c | 20 +++++++++++++++-----
1 file changed, 15 insertions(+), 5 deletions(-)
diff --git a/drivers/media/platform/vim2m.c b/drivers/media/platform/vim2m.c
index a27d3052bb62..bfb3e3eb48d1 100644
--- a/drivers/media/platform/vim2m.c
+++ b/drivers/media/platform/vim2m.c
@@ -1087,6 +1087,16 @@ static int vim2m_release(struct file *file)
return 0;
}
+static void vim2m_device_release(struct video_device *vdev)
+{
+ struct vim2m_dev *dev = container_of(vdev, struct vim2m_dev, vfd);
+
+ dprintk(dev, "Releasing last dev\n");
+ v4l2_device_unregister(&dev->v4l2_dev);
+ v4l2_m2m_release(dev->m2m_dev);
+ kfree(dev);
+}
+
static const struct v4l2_file_operations vim2m_fops = {
.owner = THIS_MODULE,
.open = vim2m_open,
@@ -1102,7 +1112,7 @@ static const struct video_device vim2m_videodev = {
.fops = &vim2m_fops,
.ioctl_ops = &vim2m_ioctl_ops,
.minor = -1,
- .release = video_device_release_empty,
+ .release = vim2m_device_release,
.device_caps = V4L2_CAP_VIDEO_M2M | V4L2_CAP_STREAMING,
};
@@ -1123,13 +1133,13 @@ static int vim2m_probe(struct platform_device *pdev)
struct video_device *vfd;
int ret;
- dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
if (ret)
- return ret;
+ goto unreg_free;
atomic_set(&dev->num_inst, 0);
mutex_init(&dev->dev_mutex);
@@ -1192,6 +1202,8 @@ static int vim2m_probe(struct platform_device *pdev)
video_unregister_device(&dev->vfd);
unreg_v4l2:
v4l2_device_unregister(&dev->v4l2_dev);
+unreg_free:
+ kfree(dev);
return ret;
}
@@ -1207,9 +1219,7 @@ static int vim2m_remove(struct platform_device *pdev)
v4l2_m2m_unregister_media_controller(dev->m2m_dev);
media_device_cleanup(&dev->mdev);
#endif
- v4l2_m2m_release(dev->m2m_dev);
video_unregister_device(&dev->vfd);
- v4l2_device_unregister(&dev->v4l2_dev);
return 0;
}
--
2.20.1
