2019-03-13 12:23:41

by Enric Balletbo i Serra

[permalink] [raw]
Subject: [RESEND PATCH] PM / devfreq: Fix static checker warning in try_then_request_governor

The patch 23c7b54ca1cd: "PM / devfreq: Fix devfreq_add_device() when
drivers are built as modules." leads to the following static checker
warning:

drivers/devfreq/devfreq.c:1043 governor_store()
warn: 'governor' can also be NULL

The reason is that the try_then_request_governor() function returns both
error pointers and NULL. It should just return error pointers, so fix
this by returning a ERR_PTR to the error intead of returning NULL.

Fixes: 23c7b54ca1cd ("PM / devfreq: Fix devfreq_add_device() when drivers are built as modules.")
Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Enric Balletbo i Serra <[email protected]>
Reviewed-by: Chanwoo Choi <[email protected]>
---
Hi,

This is a resend of [1] as seems that got lost at some point and I just
noticed that was never merged.

Thanks,
Enric

[1] https://lkml.org/lkml/2018/10/16/744


drivers/devfreq/devfreq.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 0ae3de76833b..839621b044f4 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -228,7 +228,7 @@ static struct devfreq_governor *find_devfreq_governor(const char *name)
* if is not found. This can happen when both drivers (the governor driver
* and the driver that call devfreq_add_device) are built as modules.
* devfreq_list_lock should be held by the caller. Returns the matched
- * governor's pointer.
+ * governor's pointer or an error pointer.
*/
static struct devfreq_governor *try_then_request_governor(const char *name)
{
@@ -254,7 +254,7 @@ static struct devfreq_governor *try_then_request_governor(const char *name)
/* Restore previous state before return */
mutex_lock(&devfreq_list_lock);
if (err)
- return NULL;
+ return ERR_PTR(err);

governor = find_devfreq_governor(name);
}
--
2.20.1



2019-03-14 07:48:51

by MyungJoo Ham

[permalink] [raw]
Subject: RE: [RESEND PATCH] PM / devfreq: Fix static checker warning in try_then_request_governor

>The patch 23c7b54ca1cd: "PM / devfreq: Fix devfreq_add_device() when
>drivers are built as modules." leads to the following static checker
>warning:
>
> drivers/devfreq/devfreq.c:1043 governor_store()
> warn: 'governor' can also be NULL
>
>The reason is that the try_then_request_governor() function returns both
>error pointers and NULL. It should just return error pointers, so fix
>this by returning a ERR_PTR to the error intead of returning NULL.
>
>Fixes: 23c7b54ca1cd ("PM / devfreq: Fix devfreq_add_device() when drivers are built as modules.")
>Reported-by: Dan Carpenter <[email protected]>
>Signed-off-by: Enric Balletbo i Serra <[email protected]>
>Reviewed-by: Chanwoo Choi <[email protected]>
>---
>Hi,
>
>This is a resend of [1] as seems that got lost at some point and I just
>noticed that was never merged.
>
>Thanks,
> Enric

Acked-by: MyungJoo Ham <[email protected]>

Thanks!


CHeers,
MyungJoo

2019-05-28 01:17:03

by Chanwoo Choi

[permalink] [raw]
Subject: Re: [RESEND PATCH] PM / devfreq: Fix static checker warning in try_then_request_governor

Cc: [email protected]

Dear all,

It missed to send this patch to '[email protected]'.
So, I add it to mailing list.

Regards,
Chanwoo Choi


On 19. 3. 13. 오후 9:22, Enric Balletbo i Serra wrote:
> The patch 23c7b54ca1cd: "PM / devfreq: Fix devfreq_add_device() when
> drivers are built as modules." leads to the following static checker
> warning:
>
> drivers/devfreq/devfreq.c:1043 governor_store()
> warn: 'governor' can also be NULL
>
> The reason is that the try_then_request_governor() function returns both
> error pointers and NULL. It should just return error pointers, so fix
> this by returning a ERR_PTR to the error intead of returning NULL.
>
> Fixes: 23c7b54ca1cd ("PM / devfreq: Fix devfreq_add_device() when drivers are built as modules.")
> Reported-by: Dan Carpenter <[email protected]>
> Signed-off-by: Enric Balletbo i Serra <[email protected]>
> Reviewed-by: Chanwoo Choi <[email protected]>
> ---
> Hi,
>
> This is a resend of [1] as seems that got lost at some point and I just
> noticed that was never merged.
>
> Thanks,
> Enric
>
> [1] https://lkml.org/lkml/2018/10/16/744
>
>
> drivers/devfreq/devfreq.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 0ae3de76833b..839621b044f4 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -228,7 +228,7 @@ static struct devfreq_governor *find_devfreq_governor(const char *name)
> * if is not found. This can happen when both drivers (the governor driver
> * and the driver that call devfreq_add_device) are built as modules.
> * devfreq_list_lock should be held by the caller. Returns the matched
> - * governor's pointer.
> + * governor's pointer or an error pointer.
> */
> static struct devfreq_governor *try_then_request_governor(const char *name)
> {
> @@ -254,7 +254,7 @@ static struct devfreq_governor *try_then_request_governor(const char *name)
> /* Restore previous state before return */
> mutex_lock(&devfreq_list_lock);
> if (err)
> - return NULL;
> + return ERR_PTR(err);
>
> governor = find_devfreq_governor(name);
> }
>


--
Best Regards,
Chanwoo Choi
Samsung Electronics

2019-05-28 13:09:27

by Greg Kroah-Hartman

[permalink] [raw]
Subject: Re: [RESEND PATCH] PM / devfreq: Fix static checker warning in try_then_request_governor

On Tue, May 28, 2019 at 10:15:59AM +0900, Chanwoo Choi wrote:
> Cc: [email protected]
>
> Dear all,
>
> It missed to send this patch to '[email protected]'.
> So, I add it to mailing list.

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree. Please read:
https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>