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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, USER_AGENT_SANE_1 autolearn=no 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 C2977C433ED for ; Fri, 14 May 2021 13:49:20 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 F249561476 for ; Fri, 14 May 2021 13:49:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F249561476 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id A3ED640ED4; Fri, 14 May 2021 13:49:19 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 7ysLespETYmu; Fri, 14 May 2021 13:49:17 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp4.osuosl.org (Postfix) with ESMTP id 1343E40EFF; Fri, 14 May 2021 13:49:17 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id E1995C000D; Fri, 14 May 2021 13:49:16 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [IPv6:2605:bc80:3010::133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 8085DC0001 for ; Fri, 14 May 2021 13:49:15 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 6CB8640465 for ; Fri, 14 May 2021 13:49:15 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id sVioAC1OsxIr for ; Fri, 14 May 2021 13:49:12 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by smtp2.osuosl.org (Postfix) with ESMTPS id A21A140485 for ; Fri, 14 May 2021 13:49:12 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 2A43F6736F; Fri, 14 May 2021 15:49:01 +0200 (CEST) Date: Fri, 14 May 2021 15:49:00 +0200 From: Christoph Hellwig To: Logan Gunthorpe Subject: Re: [PATCH v2 06/22] PCI/P2PDMA: Attempt to set map_type if it has not been set Message-ID: <20210514134900.GA4715@lst.de> References: <20210513223203.5542-1-logang@deltatee.com> <20210513223203.5542-7-logang@deltatee.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210513223203.5542-7-logang@deltatee.com> User-Agent: Mutt/1.5.17 (2007-11-01) Cc: linux-pci@vger.kernel.org, Dave Hansen , linux-nvme@lists.infradead.org, Stephen Bates , linux-mm@kvack.org, Jason Ekstrand , Ira Weiny , Christoph Hellwig , Minturn Dave B , Matthew Wilcox , Jason Gunthorpe , Bjorn Helgaas , Daniel Vetter , John Hubbard , linux-block@vger.kernel.org, Dan Williams , Jakowski Andrzej , Xiong Jianxin , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, Robin Murphy , Christian =?iso-8859-1?Q?K=F6nig?= X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Thu, May 13, 2021 at 04:31:47PM -0600, Logan Gunthorpe wrote: > Attempt to find the mapping type for P2PDMA pages on the first > DMA map attempt if it has not been done ahead of time. > > Previously, the mapping type was expected to be calculated ahead of > time, but if pages are to come from userspace then there's no > way to ensure the path was checked ahead of time. > > With this change it's no longer invalid to call pci_p2pdma_map_sg() > before the mapping type is calculated so drop the WARN_ON when that > is the case. Why? _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu