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=-11.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 22F59C433E0 for ; Mon, 1 Feb 2021 20:25:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E550C64E2E for ; Mon, 1 Feb 2021 20:25:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231294AbhBAUYz (ORCPT ); Mon, 1 Feb 2021 15:24:55 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:27501 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229599AbhBAUYw (ORCPT ); Mon, 1 Feb 2021 15:24:52 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612211005; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=2divzMOJAtQWbOGCxdLrJaFfqfhzDFmvPYVXeElaPz4=; b=M95YBM2rW3Gthy8vSRrbzNQDEtJxi7Q12cXdaKWZ1xRQbmMIq3snVtwBC2kfQlPI8MZDiY c5AAmy3lTAmWtEHT0+H7vu6fXAYA4e8N+9NtVRiEZhYGX+z+040Ab9dt3xk4r5k3UJt5rw X3XVuIek8YTTHag9uYxcwtXO4Hx1Rkg= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-425-_d1zn_BaO0ylK1XK1SfrXg-1; Mon, 01 Feb 2021 15:23:20 -0500 X-MC-Unique: _d1zn_BaO0ylK1XK1SfrXg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 953E819251A2; Mon, 1 Feb 2021 20:23:19 +0000 (UTC) Received: from omen.home.shazbot.org (ovpn-112-255.phx2.redhat.com [10.3.112.255]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2F4BA10013C0; Mon, 1 Feb 2021 20:23:19 +0000 (UTC) Date: Mon, 1 Feb 2021 13:23:18 -0700 From: Alex Williamson To: Steven Sistare Cc: kvm@vger.kernel.org, Cornelia Huck , Kirti Wankhede Subject: Re: [PATCH V3 0/9] vfio virtual address update Message-ID: <20210201132318.36795807@omen.home.shazbot.org> In-Reply-To: <29f7a496-f3c5-c273-538a-34ae87215e0c@oracle.com> References: <1611939252-7240-1-git-send-email-steven.sistare@oracle.com> <20210129145550.566d5369@omen.home.shazbot.org> <29f7a496-f3c5-c273-538a-34ae87215e0c@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Sat, 30 Jan 2021 11:54:03 -0500 Steven Sistare wrote: > On 1/29/2021 4:55 PM, Alex Williamson wrote: > > On Fri, 29 Jan 2021 08:54:03 -0800 > > Steve Sistare wrote: > > > >> Add interfaces that allow the underlying memory object of an iova range > >> to be mapped to a new virtual address in the host process: > >> > >> - VFIO_DMA_UNMAP_FLAG_VADDR for VFIO_IOMMU_UNMAP_DMA > >> - VFIO_DMA_MAP_FLAG_VADDR flag for VFIO_IOMMU_MAP_DMA > >> - VFIO_UPDATE_VADDR for VFIO_CHECK_EXTENSION > >> - VFIO_DMA_UNMAP_FLAG_ALL for VFIO_IOMMU_UNMAP_DMA > >> - VFIO_UNMAP_ALL for VFIO_CHECK_EXTENSION > >> > >> Unmap-vaddr invalidates the host virtual address in an iova range and blocks > >> vfio translation of host virtual addresses, but DMA to already-mapped pages > >> continues. Map-vaddr updates the base VA and resumes translation. The > >> implementation supports iommu type1 and mediated devices. Unmap-all allows > >> all ranges to be unmapped or invalidated in a single ioctl, which simplifies > >> userland code. > >> > >> This functionality is necessary for live update, in which a host process > >> such as qemu exec's an updated version of itself, while preserving its > >> guest and vfio devices. The process blocks vfio VA translation, exec's > >> its new self, mmap's the memory object(s) underlying vfio object, updates > >> the VA, and unblocks translation. For a working example that uses these > >> new interfaces, see the QEMU patch series "[PATCH V2] Live Update" at > >> https://lore.kernel.org/qemu-devel/1609861330-129855-1-git-send-email-steven.sistare@oracle.com > >> > >> Patches 1-3 define and implement the flag to unmap all ranges. > >> Patches 4-6 define and implement the flags to update vaddr. > >> Patches 7-9 add blocking to complete the implementation. > > > > Hi Steve, > > > > It looks pretty good to me, but I have some nit-picky comments that > > I'll follow-up with on the individual patches. However, I've made the > > changes I suggest in a branch that you can find here: > > > > git://github.com/awilliam/linux-vfio.git vaddr-v3 > > > > If the changes look ok, just send me an ack, I don't want to attribute > > something to you that you don't approve of. Thanks, > > All changes look good, thanks! > Do you need anything more from me on this patch series? Here's a new branch: git://github.com/awilliam/linux-vfio.git vaddr-v3.1 Extent of the changes are s/may not/cannot/ on patches 1 & 4 and addition of Connie's R-b for all (rebased to rc6). If there are any final comments, speak now. Thanks, Alex