Subject: Re: [PATCH] fpga: stratix10-soc: fix NULL vs IS_ERR() checking
To:     Miaoqian Lin <linmq006@gmail.com>
Cc:     Moritz Fischer <mdf@kernel.org>, Wu Hao <hao.wu@intel.com>,
        Xu Yilun <yilun.xu@intel.com>, linux-fpga@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20211211134332.21679-1-linmq006@gmail.com>
From:   Tom Rix <trix@redhat.com>
Message-ID: <b1186cd9-c29c-397b-080b-dcfc6b02525f@redhat.com>
Date:   Sat, 11 Dec 2021 06:05:13 -0800
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On 12/11/21 5:43 AM, Miaoqian Lin wrote:
> The stratix10_svc_allocate_memory function does not return NULL. It
> returns ERR_PTR(-ENOMEM). Use IS_ERR check the return value.
>
> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
> ---
>   drivers/fpga/stratix10-soc.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/fpga/stratix10-soc.c b/drivers/fpga/stratix10-soc.c
> index 047fd7f23706..2d2687a90ae6 100644
> --- a/drivers/fpga/stratix10-soc.c
> +++ b/drivers/fpga/stratix10-soc.c
> @@ -213,7 +213,7 @@ static int s10_ops_write_init(struct fpga_manager *mgr,
>   	/* Allocate buffers from the service layer's pool. */
>   	for (i = 0; i < NUM_SVC_BUFS; i++) {
>   		kbuf = stratix10_svc_allocate_memory(priv->chan, SVC_BUF_SIZE);
> -		if (!kbuf) {
> +		if (IS_ERR(kbuf)) {
>   			s10_free_buffers(mgr);
>   			ret = -ENOMEM;

This should also change to

ret = PTR_ERR(kbuf)

Tom

>   			goto init_done;