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=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT 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 A3723C43387 for ; Wed, 16 Jan 2019 14:10:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7E86820657 for ; Wed, 16 Jan 2019 14:10:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404294AbfAPOKr (ORCPT ); Wed, 16 Jan 2019 09:10:47 -0500 Received: from mx2.suse.de ([195.135.220.15]:33094 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1733044AbfAPOKr (ORCPT ); Wed, 16 Jan 2019 09:10:47 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id F187EAF31; Wed, 16 Jan 2019 14:10:45 +0000 (UTC) Date: Wed, 16 Jan 2019 15:10:43 +0100 From: Joerg Roedel To: "Michael S. Tsirkin" Cc: Joerg Roedel , Jason Wang , Konrad Rzeszutek Wilk , Christoph Hellwig , Jens Axboe , virtualization@lists.linux-foundation.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, jfehlig@suse.com, jon.grimm@amd.com, brijesh.singh@amd.com Subject: Re: [PATCH 3/3] virtio-blk: Consider dma_max_mapping_size() for maximum segment size Message-ID: <20190116141043.qbsdbdt72akxpdtj@suse.de> References: <20190115132257.6426-1-joro@8bytes.org> <20190115132257.6426-4-joro@8bytes.org> <20190116090355-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190116090355-mutt-send-email-mst@kernel.org> User-Agent: NeoMutt/20170421 (1.8.2) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 16, 2019 at 09:05:40AM -0500, Michael S. Tsirkin wrote: > On Tue, Jan 15, 2019 at 02:22:57PM +0100, Joerg Roedel wrote: > > + max_size = dma_max_mapping_size(&vdev->dev); > > + > > > Should this be limited to ACCESS_PLATFORM? > > I see no reason to limit this without as guest can > access any memory. Actually, yes. This should be inside a use_dma_api check. I had it in v1, but it went away without the vring layer for propagating the limit. I'll add that again. Thanks, Joerg