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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 8C38FC2D0A3 for ; Fri, 6 Nov 2020 18:24:34 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 05A40208FE for ; Fri, 6 Nov 2020 18:24:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 05A40208FE 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 silver.osuosl.org (Postfix) with ESMTP id A514A2E11D; Fri, 6 Nov 2020 18:24:33 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OamJdQ+4o3NO; Fri, 6 Nov 2020 18:24:32 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id C670920334; Fri, 6 Nov 2020 18:24:32 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id A4C71C0893; Fri, 6 Nov 2020 18:24:32 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists.linuxfoundation.org (Postfix) with ESMTP id 2010DC0889 for ; Fri, 6 Nov 2020 18:24:31 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 1807B2E11D for ; Fri, 6 Nov 2020 18:24:31 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id sVO5DwbRktz4 for ; Fri, 6 Nov 2020 18:24:29 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by silver.osuosl.org (Postfix) with ESMTPS id 8B71920334 for ; Fri, 6 Nov 2020 18:24:29 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 9DA7368B02; Fri, 6 Nov 2020 19:24:24 +0100 (CET) Date: Fri, 6 Nov 2020 19:24:24 +0100 From: Christoph Hellwig To: Konrad Rzeszutek Wilk Subject: Re: [PATCH v3] swiotlb: Adjust SWIOTBL bounce buffer size for SEV guests. Message-ID: <20201106182424.GA9330@lst.de> References: <20201104220804.21026-1-Ashish.Kalra@amd.com> <20201104221452.GA26079@char.us.oracle.com> <20201104223913.GA25311@ashkalra_ubuntu_server> <20201105174317.GA4294@char.us.oracle.com> <20201105184115.GA25261@ashkalra_ubuntu_server> <20201105190649.GB5366@char.us.oracle.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201105190649.GB5366@char.us.oracle.com> User-Agent: Mutt/1.5.17 (2007-11-01) Cc: Thomas.Lendacky@amd.com, Ashish Kalra , brijesh.singh@amd.com, ssg.sos.patches@amd.com, dave.hansen@linux-intel.com, peterz@infradead.org, x86@kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, mingo@redhat.com, bp@alien8.de, luto@kernel.org, hpa@zytor.com, tglx@linutronix.de, hch@lst.de 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, Nov 05, 2020 at 02:06:49PM -0500, Konrad Rzeszutek Wilk wrote: > . > > > Right, so I am wondering if we can do this better. > > > > > > That is you are never going to get any 32-bit devices with SEV right? That > > > is there is nothing that bounds you to always use the memory below 4GB? > > > > > > > We do support 32-bit PCIe passthrough devices with SEV. > > Ewww.. Which devices would this be? There is still some new broken shit like that that keeps appearing. GPU is pretty famouts for supporting less than 64-bit addressing, even if it isn't all the way down to 32-bit. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu