Re: [PATCH 1/1] infiniband: Remove redundant NULL check before kfree

[Doug Ledford]

> On Jun 26, 2015, at 3:09 AM, Maninder Singh <maninder1.s@xxxxxxxxxxx> wrote:
> 
> kfree(NULL) is safe and this check is probably not required
> 
> Signed-off-by: Maninder Singh <maninder1.s@xxxxxxxxxxx>
> Reviewed-by: Akhilesh Kumar <akhilesh.k@xxxxxxxxxxx>
> ---
> drivers/infiniband/hw/mlx4/main.c |    6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
> index 067a691..4e60b39 100644
> --- a/drivers/infiniband/hw/mlx4/main.c
> +++ b/drivers/infiniband/hw/mlx4/main.c
> @@ -2676,10 +2676,8 @@ static void do_slave_init(struct mlx4_ib_dev *ibdev, int slave, int do_init)
> 		dm[i] = kmalloc(sizeof (struct mlx4_ib_demux_work), GFP_ATOMIC);
> 		if (!dm[i]) {
> 			pr_err("failed to allocate memory for tunneling qp update work struct\n");
> -			for (i = 0; i < dev->caps.num_ports; i++) {
> -				if (dm[i])
> -					kfree(dm[i]);
> -			}
> +			for (i = 0; i < dev->caps.num_ports; i++)
> +				kfree(dm[i]);
> 			goto out;
> 		}
> 	}
> --
> 1.7.9.5
> 

If you are going to change this, you might as well make it 100% correct:

iâ-;
while (i >= 0)
	kfree(dm[i]);

Then you donât have to worry about whether kfree works on NULL, every item you free will be guaranteed to be non-NULL.

â
Doug Ledford <dledford@xxxxxxxxxx>
	GPG Key ID: 0E572FDD

Attachment: signature.asc
Description: Message signed with OpenPGP using GPGMail