2018-06-18 06:08:11

by Oleksandr Andrushchenko

[permalink] [raw]
Subject: [PATCH v2] drm: Replace NULL with error value in drm_prime_pages_to_sg

From: Oleksandr Andrushchenko <[email protected]>

Dan Carpenter has reported that there is the following static checker
warning:
drivers/gpu/drm/drm_prime.c:317 drm_gem_map_dma_buf()
warn: 'sgt' can also be NULL

314 sgt = obj->dev->driver->gem_prime_get_sg_table(obj);
315
316 if (!IS_ERR(sgt)) {
317 if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir,

Problematic functions are xen_drm_front_gem_get_sg_table and
drm_gem_cma_prime_get_sg_table. Fix those by replacing NULL with error value.

Signed-off-by: Oleksandr Andrushchenko <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
---
drivers/gpu/drm/drm_gem_cma_helper.c | 2 +-
drivers/gpu/drm/xen/xen_drm_front_gem.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
index 80a5115c3846..ce868ce288fb 100644
--- a/drivers/gpu/drm/drm_gem_cma_helper.c
+++ b/drivers/gpu/drm/drm_gem_cma_helper.c
@@ -436,7 +436,7 @@ struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj)

sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
if (!sgt)
- return NULL;
+ return ERR_PTR(-ENOMEM);

ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr,
cma_obj->paddr, obj->size);
diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c
index c85bfe7571cb..47ff019d3aef 100644
--- a/drivers/gpu/drm/xen/xen_drm_front_gem.c
+++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c
@@ -179,7 +179,7 @@ struct sg_table *xen_drm_front_gem_get_sg_table(struct drm_gem_object *gem_obj)
struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj);

if (!xen_obj->pages)
- return NULL;
+ return ERR_PTR(-ENOMEM);

return drm_prime_pages_to_sg(xen_obj->pages, xen_obj->num_pages);
}
--
2.17.1



2018-06-18 06:09:43

by Oleksandr Andrushchenko

[permalink] [raw]
Subject: Re: [PATCH v2] drm: Replace NULL with error value in drm_prime_pages_to_sg

On 06/18/2018 09:07 AM, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <[email protected]>
>
> Dan Carpenter has reported that there is the following static checker
> warning:
> drivers/gpu/drm/drm_prime.c:317 drm_gem_map_dma_buf()
> warn: 'sgt' can also be NULL
>
> 314 sgt = obj->dev->driver->gem_prime_get_sg_table(obj);
> 315
> 316 if (!IS_ERR(sgt)) {
> 317 if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir,
>
> Problematic functions are xen_drm_front_gem_get_sg_table and
> drm_gem_cma_prime_get_sg_table. Fix those by replacing NULL with error value.
>
> Signed-off-by: Oleksandr Andrushchenko <[email protected]>
> Reported-by: Dan Carpenter <[email protected]>
Dan, could you please review?
> ---
> drivers/gpu/drm/drm_gem_cma_helper.c | 2 +-
> drivers/gpu/drm/xen/xen_drm_front_gem.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
> index 80a5115c3846..ce868ce288fb 100644
> --- a/drivers/gpu/drm/drm_gem_cma_helper.c
> +++ b/drivers/gpu/drm/drm_gem_cma_helper.c
> @@ -436,7 +436,7 @@ struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj)
>
> sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
> if (!sgt)
> - return NULL;
> + return ERR_PTR(-ENOMEM);
>
Forgot to patch CMA helpers, thus v2
> ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr,
> cma_obj->paddr, obj->size);
> diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c
> index c85bfe7571cb..47ff019d3aef 100644
> --- a/drivers/gpu/drm/xen/xen_drm_front_gem.c
> +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c
> @@ -179,7 +179,7 @@ struct sg_table *xen_drm_front_gem_get_sg_table(struct drm_gem_object *gem_obj)
> struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj);
>
> if (!xen_obj->pages)
> - return NULL;
> + return ERR_PTR(-ENOMEM);
>
> return drm_prime_pages_to_sg(xen_obj->pages, xen_obj->num_pages);
> }


2018-06-18 12:32:04

by Dan Carpenter

[permalink] [raw]
Subject: Re: [PATCH v2] drm: Replace NULL with error value in drm_prime_pages_to_sg

On Mon, Jun 18, 2018 at 09:07:09AM +0300, Oleksandr Andrushchenko wrote:
> drivers/gpu/drm/drm_gem_cma_helper.c | 2 +-
> drivers/gpu/drm/xen/xen_drm_front_gem.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
> index 80a5115c3846..ce868ce288fb 100644
> --- a/drivers/gpu/drm/drm_gem_cma_helper.c
> +++ b/drivers/gpu/drm/drm_gem_cma_helper.c
> @@ -436,7 +436,7 @@ struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj)
>
> sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
> if (!sgt)
> - return NULL;
> + return ERR_PTR(-ENOMEM);
>
> ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr,
> cma_obj->paddr, obj->size);


If dma_get_sgtable() fails then we return NULL.

Fix that and it should be good.

regards,
dan carpenter


2018-06-18 12:33:56

by Oleksandr Andrushchenko

[permalink] [raw]
Subject: Re: [PATCH v2] drm: Replace NULL with error value in drm_prime_pages_to_sg

On 06/18/2018 03:29 PM, Dan Carpenter wrote:
> On Mon, Jun 18, 2018 at 09:07:09AM +0300, Oleksandr Andrushchenko wrote:
>> drivers/gpu/drm/drm_gem_cma_helper.c | 2 +-
>> drivers/gpu/drm/xen/xen_drm_front_gem.c | 2 +-
>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
>> index 80a5115c3846..ce868ce288fb 100644
>> --- a/drivers/gpu/drm/drm_gem_cma_helper.c
>> +++ b/drivers/gpu/drm/drm_gem_cma_helper.c
>> @@ -436,7 +436,7 @@ struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj)
>>
>> sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
>> if (!sgt)
>> - return NULL;
>> + return ERR_PTR(-ENOMEM);
>>
>> ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr,
>> cma_obj->paddr, obj->size);
>
> If dma_get_sgtable() fails then we return NULL.
>
> Fix that and it should be good.
You mean I can put your r-b with that fixed?
> regards,
> dan carpenter
>


2018-07-12 11:59:44

by Oleksandr Andrushchenko

[permalink] [raw]
Subject: Re: [PATCH v2] drm: Replace NULL with error value in drm_prime_pages_to_sg

On 06/18/2018 03:32 PM, Oleksandr Andrushchenko wrote:
> On 06/18/2018 03:29 PM, Dan Carpenter wrote:
>> On Mon, Jun 18, 2018 at 09:07:09AM +0300, Oleksandr Andrushchenko wrote:
>>> drivers/gpu/drm/drm_gem_cma_helper.c    | 2 +-
>>>   drivers/gpu/drm/xen/xen_drm_front_gem.c | 2 +-
>>>   2 files changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c
>>> b/drivers/gpu/drm/drm_gem_cma_helper.c
>>> index 80a5115c3846..ce868ce288fb 100644
>>> --- a/drivers/gpu/drm/drm_gem_cma_helper.c
>>> +++ b/drivers/gpu/drm/drm_gem_cma_helper.c
>>> @@ -436,7 +436,7 @@ struct sg_table
>>> *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj)
>>>         sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
>>>       if (!sgt)
>>> -        return NULL;
>>> +        return ERR_PTR(-ENOMEM);
>>>         ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr,
>>>                     cma_obj->paddr, obj->size);
>>
>> If dma_get_sgtable() fails then we return NULL.
>>
>> Fix that and it should be good.
> You mean I can put your r-b with that fixed?
ping
>> regards,
>> dan carpenter
>>
>


2018-07-12 12:19:05

by Dan Carpenter

[permalink] [raw]
Subject: Re: [PATCH v2] drm: Replace NULL with error value in drm_prime_pages_to_sg

On Thu, Jul 12, 2018 at 02:58:00PM +0300, Oleksandr Andrushchenko wrote:
> On 06/18/2018 03:32 PM, Oleksandr Andrushchenko wrote:
> > On 06/18/2018 03:29 PM, Dan Carpenter wrote:
> > > On Mon, Jun 18, 2018 at 09:07:09AM +0300, Oleksandr Andrushchenko wrote:
> > > > drivers/gpu/drm/drm_gem_cma_helper.c??? | 2 +-
> > > > ? drivers/gpu/drm/xen/xen_drm_front_gem.c | 2 +-
> > > > ? 2 files changed, 2 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c
> > > > b/drivers/gpu/drm/drm_gem_cma_helper.c
> > > > index 80a5115c3846..ce868ce288fb 100644
> > > > --- a/drivers/gpu/drm/drm_gem_cma_helper.c
> > > > +++ b/drivers/gpu/drm/drm_gem_cma_helper.c
> > > > @@ -436,7 +436,7 @@ struct sg_table
> > > > *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj)
> > > > ? ????? sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
> > > > ????? if (!sgt)
> > > > -??????? return NULL;
> > > > +??????? return ERR_PTR(-ENOMEM);
> > > > ? ????? ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr,
> > > > ??????????????????? cma_obj->paddr, obj->size);
> > >
> > > If dma_get_sgtable() fails then we return NULL.
> > >
> > > Fix that and it should be good.
> > You mean I can put your r-b with that fixed?
> ping

Yeah. Send the v2 patch and I'll review it.

regards,
dan carpenter