Subject: Re: [PATCH v1] drivers/net: marvell: mvpp2: fix debugfs_create_dir() return check in three functions

From: Simon Horman <[email-masked]>
Date: Sat, 15 Jul 2023 11:48:17 +0100

On Thu, Jul 13, 2023 at 12:45:07PM +0800, Minjie Du wrote:
> Make IS_ERR() judge the debugfs_create_dir() function return
> in mvpp2_dbgfs_c2_entry_init(), mvpp2_dbgfs_flow_tbl_entry_init()
>  and mvpp2_dbgfs_cls_init()
> Line 562 deletes the space because checkpatch reports an error.
> 
> Signed-off-by: Minjie Du <[email-masked]>
> ---
>  drivers/net/ethernet/marvell/mvpp2/mvpp2_debugfs.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_debugfs.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_debugfs.c
> index 75e83ea2a..37bff3304 100644
> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_debugfs.c
> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_debugfs.c
> @@ -559,7 +559,7 @@ static int mvpp2_dbgfs_prs_entry_init(struct dentry *parent,
>  			    &mvpp2_dbgfs_prs_hits_fops);
>  
>  	debugfs_create_file("pmap", 0444, prs_entry_dir, entry,
> -			     &mvpp2_dbgfs_prs_pmap_fops);
> +			    &mvpp2_dbgfs_prs_pmap_fops);

Unfortunately net-next does not accept patches for Checkpatch warnings
of this nature.

>  
>  	return 0;
>  }
> @@ -593,7 +593,7 @@ static int mvpp2_dbgfs_c2_entry_init(struct dentry *parent,
>  	sprintf(c2_entry_name, "%03d", id);
>  
>  	c2_entry_dir = debugfs_create_dir(c2_entry_name, parent);
> -	if (!c2_entry_dir)
> +	if (IS_ERR(c2_entry_dir))
>  		return -ENOMEM;

As per the comment above debugfs_create_dir(), it is not
expected to return an error, and in general callers should
ignore the return value.

I expect a good approach here is to simply remove the error handling
for debugfs_create_dir(). e.g.

-	if (!c2_entry_dir)
-		return -ENOMEM;

-- 
pw-bot: changes-requested