* [PATCH 0/1] media: saa7146: don't use mutex_lock_interruptible in
@ 2012-12-11 3:05 Cyril Roelandt
2012-12-11 3:05 ` [PATCH 1/1] media: saa7146: don't use mutex_lock_interruptible() in device_release() Cyril Roelandt
0 siblings, 1 reply; 3+ messages in thread
From: Cyril Roelandt @ 2012-12-11 3:05 UTC (permalink / raw)
To: linux-kernel
Cc: kernel-janitors, michael, mchehab, linux-media, Cyril Roelandt
This is the same kind of bug as the one fixed by
ddc43d6dc7df0849fe41b91460fa76145cf87b67 : mutex_lock() must be used in the
device_release file operation in order for all resources to be freed, since
returning -RESTARTSYS has no effect here.
I stole the commit log from Sylwester Nawrocki, who fixed a few of these issues,
since I could not formulate it better.
---
Cyril Roelandt (1):
media: saa7146: don't use mutex_lock_interruptible() in
device_release().
drivers/media/common/saa7146/saa7146_fops.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--
1.7.10.4
^ permalink raw reply [flat|nested] 3+ messages in thread
* [PATCH 1/1] media: saa7146: don't use mutex_lock_interruptible() in device_release().
2012-12-11 3:05 [PATCH 0/1] media: saa7146: don't use mutex_lock_interruptible in Cyril Roelandt
@ 2012-12-11 3:05 ` Cyril Roelandt
2012-12-11 7:22 ` Hans Verkuil
0 siblings, 1 reply; 3+ messages in thread
From: Cyril Roelandt @ 2012-12-11 3:05 UTC (permalink / raw)
To: linux-kernel
Cc: kernel-janitors, michael, mchehab, linux-media, Cyril Roelandt
Use uninterruptible mutex_lock in the release() file op to make sure all
resources are properly freed when a process is being terminated. Returning
-ERESTARTSYS has no effect for a terminating process and this may cause driver
resources not to be released.
This was found using the following semantic patch (http://coccinelle.lip6.fr/):
<spml>
@r@
identifier fops;
identifier release_func;
@@
static const struct v4l2_file_operations fops = {
.release = release_func
};
@depends on r@
identifier r.release_func;
expression E;
@@
static int release_func(...)
{
...
- if (mutex_lock_interruptible(E)) return -ERESTARTSYS;
+ mutex_lock(E);
...
}
</spml>
Signed-off-by: Cyril Roelandt <tipecaml@gmail.com>
---
drivers/media/common/saa7146/saa7146_fops.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/media/common/saa7146/saa7146_fops.c b/drivers/media/common/saa7146/saa7146_fops.c
index b3890bd..0afe98d 100644
--- a/drivers/media/common/saa7146/saa7146_fops.c
+++ b/drivers/media/common/saa7146/saa7146_fops.c
@@ -265,8 +265,7 @@ static int fops_release(struct file *file)
DEB_EE("file:%p\n", file);
- if (mutex_lock_interruptible(vdev->lock))
- return -ERESTARTSYS;
+ mutex_lock(vdev->lock);
if (vdev->vfl_type == VFL_TYPE_VBI) {
if (dev->ext_vv_data->capabilities & V4L2_CAP_VBI_CAPTURE)
--
1.7.10.4
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH 1/1] media: saa7146: don't use mutex_lock_interruptible() in device_release().
2012-12-11 3:05 ` [PATCH 1/1] media: saa7146: don't use mutex_lock_interruptible() in device_release() Cyril Roelandt
@ 2012-12-11 7:22 ` Hans Verkuil
0 siblings, 0 replies; 3+ messages in thread
From: Hans Verkuil @ 2012-12-11 7:22 UTC (permalink / raw)
To: Cyril Roelandt
Cc: linux-kernel, kernel-janitors, michael, mchehab, linux-media
On Tue December 11 2012 04:05:28 Cyril Roelandt wrote:
> Use uninterruptible mutex_lock in the release() file op to make sure all
> resources are properly freed when a process is being terminated. Returning
> -ERESTARTSYS has no effect for a terminating process and this may cause driver
> resources not to be released.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Thanks!
Hans
> This was found using the following semantic patch (http://coccinelle.lip6.fr/):
>
> <spml>
> @r@
> identifier fops;
> identifier release_func;
> @@
> static const struct v4l2_file_operations fops = {
> .release = release_func
> };
>
> @depends on r@
> identifier r.release_func;
> expression E;
> @@
> static int release_func(...)
> {
> ...
> - if (mutex_lock_interruptible(E)) return -ERESTARTSYS;
> + mutex_lock(E);
> ...
> }
> </spml>
>
> Signed-off-by: Cyril Roelandt <tipecaml@gmail.com>
> ---
> drivers/media/common/saa7146/saa7146_fops.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/media/common/saa7146/saa7146_fops.c b/drivers/media/common/saa7146/saa7146_fops.c
> index b3890bd..0afe98d 100644
> --- a/drivers/media/common/saa7146/saa7146_fops.c
> +++ b/drivers/media/common/saa7146/saa7146_fops.c
> @@ -265,8 +265,7 @@ static int fops_release(struct file *file)
>
> DEB_EE("file:%p\n", file);
>
> - if (mutex_lock_interruptible(vdev->lock))
> - return -ERESTARTSYS;
> + mutex_lock(vdev->lock);
>
> if (vdev->vfl_type == VFL_TYPE_VBI) {
> if (dev->ext_vv_data->capabilities & V4L2_CAP_VBI_CAPTURE)
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2012-12-11 7:23 UTC | newest]
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2012-12-11 3:05 [PATCH 0/1] media: saa7146: don't use mutex_lock_interruptible in Cyril Roelandt
2012-12-11 3:05 ` [PATCH 1/1] media: saa7146: don't use mutex_lock_interruptible() in device_release() Cyril Roelandt
2012-12-11 7:22 ` Hans Verkuil
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