Re: [PATCH] platform/mellanox: Add a null pointer check in mlxbf_pmc_create_groups

[Kunwu Chan]

Thanks for your reply.

Cause i don't know how to deal with in some scenario，such as in 
'mlxbf_pmc_init_perftype_counter', when 'attr->dev_attr.attr.name' is 
null, should return '-ENOMEM' or 'continue' the loop?

So I'm going to solve it one by one.

Thanks again,
Kunwu

On 2023/11/28 17:51, Ilpo Järvinen wrote:
> On Mon, 27 Nov 2023, Kunwu Chan wrote:
>
> > devm_kasprintf() returns a pointer to dynamically allocated memory
> > which can be NULL upon failure.
> >
> > Fixes: 1a218d312e65 ("platform/mellanox: mlxbf-pmc: Add Mellanox BlueField PMC driver")
> > Signed-off-by: Kunwu Chan <chentao@xxxxxxxxxx>
> > ---
> >   drivers/platform/mellanox/mlxbf-pmc.c | 2 ++
> >   1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/platform/mellanox/mlxbf-pmc.c b/drivers/platform/mellanox/mlxbf-pmc.c
> > index 0b427fc24a96..59bbe5e13f6b 100644
> > --- a/drivers/platform/mellanox/mlxbf-pmc.c
> > +++ b/drivers/platform/mellanox/mlxbf-pmc.c
> > @@ -1882,6 +1882,8 @@ static int mlxbf_pmc_create_groups(struct device *dev, int blk_num)
> >   	pmc->block[blk_num].block_attr_grp.attrs = pmc->block[blk_num].block_attr;
> >   	pmc->block[blk_num].block_attr_grp.name = devm_kasprintf(
> >   		dev, GFP_KERNEL, pmc->block_name[blk_num]);
> > +	if (!pmc->block[blk_num].block_attr_grp.name)
> > +		return -ENOMEM;
> >   	pmc->groups[pmc->group_num] = &pmc->block[blk_num].block_attr_grp;
> >   	pmc->group_num++;
>
> I'm totally lost, why did you fix only one devm_kasprintf() location?
> Don't all of them need this check?