Login | Register For Free | Help
Search for: (Advanced)

Mailing List Archive: ivtv: devel

[PATCH 1/1] VIDEO: ivtvfb, remove unneeded NULL test

 

 

ivtv devel RSS feed   Index | Next | Previous | View Threaded


jslaby at suse

Jul 19, 2010, 10:39 AM

Post #1 of 2 (669 views)
Permalink
[PATCH 1/1] VIDEO: ivtvfb, remove unneeded NULL test

Stanse found that in ivtvfb_callback_cleanup and ivtvfb_callback_init
there are unneeded tests for itv being NULL. But itv is initialized
as container_of with non-zero offset in those functions, so it is
never NULL (even if v4l2_dev is). This was found because itv is
dereferenced earlier than the test.

Signed-off-by: Jiri Slaby <jslaby [at] suse>
Cc: Andy Walls <awalls [at] md>
Cc: Mauro Carvalho Chehab <mchehab [at] infradead>
Cc: Tejun Heo <tj [at] kernel>
Cc: Ian Armstrong <ian [at] iarmst>
Cc: ivtv-devel [at] ivtvdriver
Cc: linux-media [at] vger
---
drivers/media/video/ivtv/ivtvfb.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/video/ivtv/ivtvfb.c b/drivers/media/video/ivtv/ivtvfb.c
index 9ff3425..9c77bfa 100644
--- a/drivers/media/video/ivtv/ivtvfb.c
+++ b/drivers/media/video/ivtv/ivtvfb.c
@@ -1203,7 +1203,7 @@ static int __init ivtvfb_callback_init(struct device *dev, void *p)
struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
struct ivtv *itv = container_of(v4l2_dev, struct ivtv, v4l2_dev);

- if (itv && (itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT)) {
+ if (itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT) {
if (ivtvfb_init_card(itv) == 0) {
IVTVFB_INFO("Framebuffer registered on %s\n",
itv->v4l2_dev.name);
@@ -1219,7 +1219,7 @@ static int ivtvfb_callback_cleanup(struct device *dev, void *p)
struct ivtv *itv = container_of(v4l2_dev, struct ivtv, v4l2_dev);
struct osd_info *oi = itv->osd_info;

- if (itv && (itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT)) {
+ if (itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT) {
if (unregister_framebuffer(&itv->osd_info->ivtvfb_info)) {
IVTVFB_WARN("Framebuffer %d is in use, cannot unload\n",
itv->instance);
--
1.7.1



_______________________________________________
ivtv-devel mailing list
ivtv-devel [at] ivtvdriver
http://ivtvdriver.org/mailman/listinfo/ivtv-devel


awalls at md

Jul 19, 2010, 2:39 PM

Post #2 of 2 (616 views)
Permalink
Re: [PATCH 1/1] VIDEO: ivtvfb, remove unneeded NULL test [In reply to]

On Mon, 2010-07-19 at 19:39 +0200, Jiri Slaby wrote:
> Stanse found that in ivtvfb_callback_cleanup and ivtvfb_callback_init
> there are unneeded tests for itv being NULL. But itv is initialized
> as container_of with non-zero offset in those functions, so it is
> never NULL (even if v4l2_dev is). This was found because itv is
> dereferenced earlier than the test.
>
> Signed-off-by: Jiri Slaby <jslaby [at] suse>
> Cc: Andy Walls <awalls [at] md>

Looks fine to me.

Reviewed-by: Andy Walls <awalls [at] md>

Regards,
Andy

> Cc: Mauro Carvalho Chehab <mchehab [at] infradead>
> Cc: Tejun Heo <tj [at] kernel>
> Cc: Ian Armstrong <ian [at] iarmst>
> Cc: ivtv-devel [at] ivtvdriver
> Cc: linux-media [at] vger
> ---
> drivers/media/video/ivtv/ivtvfb.c | 4 ++--
> 1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/video/ivtv/ivtvfb.c b/drivers/media/video/ivtv/ivtvfb.c
> index 9ff3425..9c77bfa 100644
> --- a/drivers/media/video/ivtv/ivtvfb.c
> +++ b/drivers/media/video/ivtv/ivtvfb.c
> @@ -1203,7 +1203,7 @@ static int __init ivtvfb_callback_init(struct device *dev, void *p)
> struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
> struct ivtv *itv = container_of(v4l2_dev, struct ivtv, v4l2_dev);
>
> - if (itv && (itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT)) {
> + if (itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT) {
> if (ivtvfb_init_card(itv) == 0) {
> IVTVFB_INFO("Framebuffer registered on %s\n",
> itv->v4l2_dev.name);
> @@ -1219,7 +1219,7 @@ static int ivtvfb_callback_cleanup(struct device *dev, void *p)
> struct ivtv *itv = container_of(v4l2_dev, struct ivtv, v4l2_dev);
> struct osd_info *oi = itv->osd_info;
>
> - if (itv && (itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT)) {
> + if (itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT) {
> if (unregister_framebuffer(&itv->osd_info->ivtvfb_info)) {
> IVTVFB_WARN("Framebuffer %d is in use, cannot unload\n",
> itv->instance);



_______________________________________________
ivtv-devel mailing list
ivtv-devel [at] ivtvdriver
http://ivtvdriver.org/mailman/listinfo/ivtv-devel

ivtv devel RSS feed   Index | Next | Previous | View Threaded
 
 


Interested in having your list archived? Contact Gossamer Threads
 
  Web Applications & Managed Hosting Powered by Gossamer Threads Inc.