Re: [PATCH 2/2] [media] vb2: Fix error handling in '__vb2_buf_mem_alloc'

[Sakari Ailus]

Hi Christophe,

On Sun, Apr 23, 2017 at 11:40:30PM +0200, Christophe JAILLET wrote:
> 'call_ptr_memop' can return NULL, so we must test its return value with
> 'IS_ERR_OR_NULL'. Otherwise, the test 'if (mem_priv)' is meaningless.
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> ---
> Note that error checking after 'call_ptr_memop' calls is not consistent
> in this file. I guess that 'IS_ERR_OR_NULL' should be used everywhere
> and that the corresponding error handling code should be tweaked just as
> the code in this function.
> ---
>  drivers/media/v4l2-core/videobuf2-core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c
> index c0175ea7e7ad..d1d3f5dd57b9 100644
> --- a/drivers/media/v4l2-core/videobuf2-core.c
> +++ b/drivers/media/v4l2-core/videobuf2-core.c
> @@ -210,7 +210,7 @@ static int __vb2_buf_mem_alloc(struct vb2_buffer *vb)
>  		mem_priv = call_ptr_memop(vb, alloc,
>  				q->alloc_devs[plane] ? : q->dev,
>  				q->dma_attrs, size, dma_dir, q->gfp_flags);
> -		if (IS_ERR(mem_priv)) {
> +		if (IS_ERR_OR_NULL(mem_priv)) {
>  			if (mem_priv)
>  				ret = PTR_ERR(mem_priv);
>  			goto free;

If NULL will always equate -ENOMEM, shouldn't call_ptr_memop() be changed
instead to convert NULL to ERR_PTR(-ENOMEM)?

-- 
Regards,

Sakari Ailus
e-mail: sakari.ailus@xxxxxx	XMPP: sailus@xxxxxxxxxxxxxx