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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 ACFD3C12002 for ; Fri, 16 Jul 2021 06:33:56 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4BE78613E7 for ; Fri, 16 Jul 2021 06:33:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4BE78613E7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4GR1fW0DYTz3bl9 for ; Fri, 16 Jul 2021 16:33:55 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=verein.lst.de; envelope-from=hch@lst.de; receiver=) Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4GR1f80Lgqz2yLZ for ; Fri, 16 Jul 2021 16:33:36 +1000 (AEST) Received: by verein.lst.de (Postfix, from userid 2407) id C874467373; Fri, 16 Jul 2021 08:33:32 +0200 (CEST) Date: Fri, 16 Jul 2021 08:33:32 +0200 From: Christoph Hellwig To: Logan Gunthorpe Subject: Re: [PATCH v1 16/16] dma-mapping: Disallow .map_sg operations from returning zero on error Message-ID: <20210716063332.GD13345@lst.de> References: <20210715164544.6827-1-logang@deltatee.com> <20210715164544.6827-17-logang@deltatee.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210715164544.6827-17-logang@deltatee.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-s390@vger.kernel.org, linux-ia64@vger.kernel.org, linux-parisc@vger.kernel.org, Robin Murphy , Martin Oliveira , linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, linux-alpha@vger.kernel.org, sparclinux@vger.kernel.org, xen-devel@lists.xenproject.org, Stephen Bates , linuxppc-dev@lists.ozlabs.org, Christoph Hellwig , linux-arm-kernel@lists.infradead.org, Marek Szyprowski Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Thu, Jul 15, 2021 at 10:45:44AM -0600, Logan Gunthorpe wrote: > @@ -194,6 +194,8 @@ static int __dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, > else > ents = ops->map_sg(dev, sg, nents, dir, attrs); > > + WARN_ON_ONCE(ents == 0); Turns this into a negative error code while we're at it, just to keep the callers sane?