Date:   Tue, 4 Jan 2022 10:46:23 -0700
From:   Mathieu Poirier <mathieu.poirier@linaro.org>
To:     Miaoqian Lin <linmq006@gmail.com>
Cc:     Ohad Ben-Cohen <ohad@wizery.com>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] remoteproc: Fix NULL vs IS_ERR() checking in
 rproc_create_trace_file
Message-ID: <20220104174623.GA540353@p14s>
References: <20211227090645.18600-1-linmq006@gmail.com>
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In-Reply-To: <20211227090645.18600-1-linmq006@gmail.com>
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Good morning,

On Mon, Dec 27, 2021 at 09:06:45AM +0000, Miaoqian Lin wrote:
> The debugfs_create_file() function doesn't return NULL.
> It returns error pointers.

You are correct.

> 
> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
> ---
>  drivers/remoteproc/remoteproc_debugfs.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/remoteproc/remoteproc_debugfs.c b/drivers/remoteproc/remoteproc_debugfs.c
> index b5a1e3b697d9..a2409fe2f57b 100644
> --- a/drivers/remoteproc/remoteproc_debugfs.c
> +++ b/drivers/remoteproc/remoteproc_debugfs.c
> @@ -390,7 +390,7 @@ struct dentry *rproc_create_trace_file(const char *name, struct rproc *rproc,
>  
>  	tfile = debugfs_create_file(name, 0400, rproc->dbg_dir, trace,
>  				    &trace_rproc_ops);
> -	if (!tfile) {
> +	if (IS_ERR(tfile)) {
>  		dev_err(&rproc->dev, "failed to create debugfs trace entry\n");
>  		return NULL;

Please return PTR_ERR(tfile) and fix rproc_handle_trace() to do the right error
check and propagate the error code if needed.

Thanks,
Mathieu

>  	}
> -- 
> 2.17.1
>