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 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2F0C0C7EE25 for ; Wed, 7 Jun 2023 13:13:23 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.544770.850757 (Exim 4.92) (envelope-from ) id 1q6syF-0003Oh-Hu; Wed, 07 Jun 2023 13:13:03 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 544770.850757; Wed, 07 Jun 2023 13:13:03 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1q6syF-0003Oa-Ef; Wed, 07 Jun 2023 13:13:03 +0000 Received: by outflank-mailman (input) for mailman id 544770; Wed, 07 Jun 2023 13:13:02 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1q6syE-0003OU-Q8 for xen-devel@lists.xenproject.org; Wed, 07 Jun 2023 13:13:02 +0000 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 06f042b7-0535-11ee-8611-37d641c3527e; Wed, 07 Jun 2023 15:13:00 +0200 (CEST) Received: by verein.lst.de (Postfix, from userid 2407) id 33B3F6732D; Wed, 7 Jun 2023 15:12:58 +0200 (CEST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 06f042b7-0535-11ee-8611-37d641c3527e Date: Wed, 7 Jun 2023 15:12:57 +0200 From: Christoph Hellwig To: Juergen Gross Cc: Marek =?iso-8859-1?Q?Marczykowski-G=F3recki?= , Christoph Hellwig , Stefano Stabellini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Ben Skeggs , Karol Herbst , Lyude Paul , xen-devel@lists.xenproject.org, iommu@lists.linux.dev, linux-kernel@vger.kernel.org, nouveau@lists.freedesktop.org Subject: Re: [PATCH 2/4] x86: always initialize xen-swiotlb when xen-pcifront is enabling Message-ID: <20230607131257.GB19206@lst.de> References: <20230518134253.909623-1-hch@lst.de> <20230518134253.909623-3-hch@lst.de> <20230519040405.GA10818@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) On Mon, May 22, 2023 at 10:37:09AM +0200, Juergen Gross wrote: > In normal cases PCI passthrough in PV guests requires to start the guest > with e820_host=1. So it should be rather easy to limit allocating the > 64MB in PV guests to the cases where the memory map has non-RAM regions > especially in the first 1MB of the memory. > > This will cover even hotplug cases. The only case not covered would be a > guest started with e820_host=1 even if no PCI passthrough was planned. > But this should be rather rare (at least I hope so). So is this an ACK for the patch and can we go ahead with it? (I'd still like to merge swiotlb-xen into swiotlb eventually, but it's probably not going to happen this merge window)