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=-13.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, 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 1EC6FC433E6 for ; Mon, 21 Dec 2020 15:27:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DEF2D22C97 for ; Mon, 21 Dec 2020 15:27:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726429AbgLUP13 (ORCPT ); Mon, 21 Dec 2020 10:27:29 -0500 Received: from vps0.lunn.ch ([185.16.172.187]:35716 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725497AbgLUP12 (ORCPT ); Mon, 21 Dec 2020 10:27:28 -0500 Received: from andrew by vps0.lunn.ch with local (Exim 4.94) (envelope-from ) id 1krN5B-00D9ko-LI; Mon, 21 Dec 2020 16:26:45 +0100 Date: Mon, 21 Dec 2020 16:26:45 +0100 From: Andrew Lunn To: Masahiro Yamada Cc: "David S . Miller" , Jakub Kicinski , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Miguel Ojeda , Arnd Bergmann , Heiner Kallweit Subject: Re: [PATCH] net: lantiq_etop: check the result of request_irq() Message-ID: <20201221152645.GH3026679@lunn.ch> References: <20201221054323.247483-1-masahiroy@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20201221054323.247483-1-masahiroy@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 21, 2020 at 02:43:23PM +0900, Masahiro Yamada wrote: > The declaration of request_irq() in is marked as > __must_check. > > Without the return value check, I see the following warnings: > > drivers/net/ethernet/lantiq_etop.c: In function 'ltq_etop_hw_init': > drivers/net/ethernet/lantiq_etop.c:273:4: warning: ignoring return value of 'request_irq', declared with attribute warn_unused_result [-Wunused-result] >   273 |    request_irq(irq, ltq_etop_dma_irq, 0, "etop_tx", priv); >       |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > drivers/net/ethernet/lantiq_etop.c:281:4: warning: ignoring return value of 'request_irq', declared with attribute warn_unused_result [-Wunused-result] >   281 |    request_irq(irq, ltq_etop_dma_irq, 0, "etop_rx", priv); >       |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Reported-by: Miguel Ojeda > Signed-off-by: Masahiro Yamada > --- > > drivers/net/ethernet/lantiq_etop.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/ethernet/lantiq_etop.c b/drivers/net/ethernet/lantiq_etop.c > index 2d0c52f7106b..960494f9752b 100644 > --- a/drivers/net/ethernet/lantiq_etop.c > +++ b/drivers/net/ethernet/lantiq_etop.c > @@ -264,13 +264,18 @@ ltq_etop_hw_init(struct net_device *dev) > for (i = 0; i < MAX_DMA_CHAN; i++) { > int irq = LTQ_DMA_CH0_INT + i; > struct ltq_etop_chan *ch = &priv->ch[i]; > + int ret; > > ch->idx = ch->dma.nr = i; > ch->dma.dev = &priv->pdev->dev; > > if (IS_TX(i)) { > ltq_dma_alloc_tx(&ch->dma); > - request_irq(irq, ltq_etop_dma_irq, 0, "etop_tx", priv); > + ret = request_irq(irq, ltq_etop_dma_irq, 0, "etop_tx", priv); > + if (ret) { > + netdev_err(dev, "failed to request irq\n"); > + return ret; You need to cleanup what ltq_dma_alloc_tx() did. > + } > } else if (IS_RX(i)) { > ltq_dma_alloc_rx(&ch->dma); > for (ch->dma.desc = 0; ch->dma.desc < LTQ_DESC_NUM; > @@ -278,7 +283,11 @@ ltq_etop_hw_init(struct net_device *dev) > if (ltq_etop_alloc_skb(ch)) > return -ENOMEM; > ch->dma.desc = 0; > - request_irq(irq, ltq_etop_dma_irq, 0, "etop_rx", priv); > + ret = request_irq(irq, ltq_etop_dma_irq, 0, "etop_rx", priv); > + if (ret) { > + netdev_err(dev, "failed to request irq\n"); > + return ret; And here you need to cleanup ltq_dma_alloc_rx(). Andrew