Commit fb069a5d132fb926ed17af3211a114ac7cf27d7a introduced a private portion in struct device that is dynamically allocated on demand, such as when a driver stores a private pointer in the device's structure using dev_set_drvdata. video_register_device memsets the device structure embedded in the video_device structure to 0, just in case the caller forgot to do so. If the caller stored private data in the device structure before registering the video device, this sets the device's private portion pointer to NULL without freeing the memory. Remove the memset to 0. Callers are supposed to have done it already. Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> --- drivers/media/video/v4l2-dev.c | 5 ----- 1 files changed, 0 insertions(+), 5 deletions(-) This is mostly an RFC patch (although it can be applied as-is). Zeroing the device structure is definitely not a good idea. Of course drivers need to be reviewed to make sure they zero it themselves before calling video_set_drvdata. Another approach would be to add a priv argument to video_register_device. All drivers would still need to be converted. I favor the approach taken in this patch (coupled with a review of the drivers) because drivers should really zero the structure. This is a good occasion to clean drivers up and fix a few bugs. diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c index 13a899d..1fec852 100644 --- a/drivers/media/video/v4l2-dev.c +++ b/drivers/media/video/v4l2-dev.c @@ -412,7 +412,6 @@ static int __video_register_device(struct video_device *vdev, int type, int nr, int minor_offset = 0; int minor_cnt = VIDEO_NUM_DEVICES; const char *name_base; - void *priv = video_get_drvdata(vdev); /* A minor value of -1 marks this video device as never having been registered */ @@ -536,10 +535,6 @@ static int __video_register_device(struct video_device *vdev, int type, int nr, } /* Part 4: register the device with sysfs */ - memset(&vdev->dev, 0, sizeof(vdev->dev)); - /* The memset above cleared the device's drvdata, so - put back the copy we made earlier. */ - video_set_drvdata(vdev, priv); vdev->dev.class = &video_class; vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor); if (vdev->parent) -- 1.6.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
