From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8AFABC282E3 for ; Mon, 27 May 2019 02:33:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 617352075C for ; Mon, 27 May 2019 02:33:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726139AbfE0Cdg (ORCPT ); Sun, 26 May 2019 22:33:36 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:17162 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725973AbfE0Cdg (ORCPT ); Sun, 26 May 2019 22:33:36 -0400 Received: from DGGEMS404-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id D7F0E9D3FE75A93C40BB; Mon, 27 May 2019 10:33:33 +0800 (CST) Received: from [127.0.0.1] (10.177.96.96) by DGGEMS404-HUB.china.huawei.com (10.3.19.204) with Microsoft SMTP Server id 14.3.439.0; Mon, 27 May 2019 10:33:29 +0800 Subject: =?UTF-8?Q?Re:_[PATCH_net]_staging:_Remove_set_but_not_used_variable?= =?UTF-8?B?IOKAmHN0YXR1c+KAmQ==?= To: Sven Van Asbroeck References: <20190525042642.78482-1-maowenan@huawei.com> CC: Greg KH , Jeremy Sowden , , Linux Kernel Mailing List , , "Matt Sickler" From: maowenan Message-ID: <05c9bfac-c3ad-5889-8f47-0e6f53844a76@huawei.com> Date: Mon, 27 May 2019 10:33:27 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.96.96] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019/5/25 20:59, Sven Van Asbroeck wrote: > On Sat, May 25, 2019 at 12:20 AM Mao Wenan wrote: >> >> The variable 'status' is not used any more, remve it. > >> /* do the transfers for this message */ >> list_for_each_entry(transfer, &m->transfers, transfer_list) { >> if (transfer->tx_buf == NULL && transfer->rx_buf == NULL && transfer->len) { >> - status = -EINVAL; >> break; >> } > > This looks like an error condition that's not reported to the spi core. > > Instead of removing the status variable (which also removes the error value!), > maybe this should be reported to the spi core instead ? > > Other spi drivers appear to do the following on the error path: > m->status = status; > return status; I have reviewed the code again, and it is good idea to store m->status in error path, like below? @@ -374,7 +374,7 @@ kp_spi_transfer_one_message(struct spi_master *master, struct spi_message *m) list_for_each_entry(transfer, &m->transfers, transfer_list) { if (transfer->tx_buf == NULL && transfer->rx_buf == NULL && transfer->len) { status = -EINVAL; - break; + goto error; } /* transfer */ @@ -412,7 +412,7 @@ kp_spi_transfer_one_message(struct spi_master *master, struct spi_message *m) if (count != transfer->len) { status = -EIO; - break; + goto error; } } ... /* done work */ spi_finalize_current_message(master); return 0; + + error: + m->status = status; + return status; } > >> >> @@ -370,7 +368,6 @@ kp_spi_transfer_one_message(struct spi_master *master, struct spi_message *m) >> >> if (count != transfer->len) { >> - status = -EIO; >> break; > > Same issue here. > >