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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 32671C04AB4 for ; Fri, 17 May 2019 13:24:40 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F415420833 for ; Fri, 17 May 2019 13:24:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (4096-bit key) header.d=crudebyte.com header.i=@crudebyte.com header.b="YORKIrSf" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F415420833 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=nongnu.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:48604 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hRcql-00034N-5k for qemu-devel@archiver.kernel.org; Fri, 17 May 2019 09:24:39 -0400 Received: from eggs.gnu.org ([209.51.188.92]:58850) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hRcpM-0002BB-7n for qemu-devel@nongnu.org; Fri, 17 May 2019 09:23:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hRcpK-00060B-Mr for qemu-devel@nongnu.org; Fri, 17 May 2019 09:23:12 -0400 Received: from kylie.crudebyte.com ([5.189.157.229]:57903) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hRcpK-0005wW-5i for qemu-devel@nongnu.org; Fri, 17 May 2019 09:23:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=crudebyte.com; s=kylie; h=Content-Type:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=ZzrHE0i4kD6viiCvYk1mQqz6IEw8tjSauLNmfvunQog=; b=YORKIrSfMo6aHxNUUfKOMOFmna 5MeL7ssWDyoU8FYsuIpkLM8MgdsY2BRUMG6rFoEm01KYEZuT7cis3kByMspuDCcQQ1y48CzQSCO4e GuAF4ShidGSaC5+4K3UQtr0PAM7OElusq0YGB+0PVnZOxyasENQtKnnpCnNQZV1sde2VzwVo4ObFW GU7Bfs4KdgJjk6NTIAn2eq8G08xEIeBC1ccdEbYzem01CgdjOLVE5bf9BT44yW6HMDnlaehY5DgQk TM1y8mRRJ/mLXpGXheHHHvm49Rc4WZvZBRxDANkAUcQImMhBpxPr9p/dxFvoOIPMZDsdPKZmgQRkT yBuYVJUthdYWlEP1KgqNyEIAbjRgkNuSHitBuLKdik+G4w0NoR3bcAfwQjBdH4S2GxAiUQhlaxACL nRlGtgKrVgW6sbc3ZSdxZaIj5cyw5W8YWZyKty5G2u6gdotPoC9VuLyFRk+uUQJfQsGwNimpEz9tu SBYUDQz9AuoAyfKSBenV4m0sgyrjmFsdtZ1IOIB73phgcXH8rlXFEtOuC2k/POFGNppztqfwxu533 FR7uEKTmgfdeyS01g6ydooFItYXBzTZKNcgzhJKSqDVOSm8xxgw/u+FeFuLrJiGv88yUfsSm5Kj4A 8qLNUsESI7OHXbV++on0a1AtKMfAnhCbxbNbhNuUw=; To: qemu-devel@nongnu.org Date: Fri, 17 May 2019 15:23:01 +0200 Message-ID: <1723391.cvQaRflHa6@silver> In-Reply-To: <20190517143029.25454663@bahia.lan> References: <590216e2666653bac21d950aaba98f87d0a53324.1557093245.git.qemu_oss@crudebyte.com> <8706106.MIJVTSuNya@silver> <20190517143029.25454663@bahia.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 5.189.157.229 Subject: Re: [Qemu-devel] [libvirt patch] qemu: adds support for virtfs 9p argument 'vii' X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Christian Schoenebeck via Qemu-devel Reply-To: Christian Schoenebeck Cc: Daniel =?ISO-8859-1?Q?P=2E_Berrang=E9?= , Christian Schoenebeck , Greg Kurz , Antonios Motakis Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Freitag, 17. Mai 2019 14:30:29 CEST Greg Kurz wrote: > Then, we come to the bulk problem: how to handle the case where we > have multiple devices involved in a directory we want to share ? > Antonios's proposal is a clever way to address the collisions, but > your work proves it isn't enough... With the patch set I have right now, things finally bahave smooth. > Before going forward, I'd like > to consider another approach. > > What about: > > 1) de-compose the shared directory on a per-device basis, > ie. identify all mount points under the shared directory > > 2) expose found mount points separately, each with its onw 9p device > > 3) re-compose the directory tree within the guest using the same topology > as the host > > ie. if you want to share /vm/fs and > > /vm/fs on device A > /vm/fs/shares on device B > /vm/fs/tmp on device C > > you would start QEMU with > > -fsdev local,path=/vm/fs,id=fsdev0... \ > -device virtio-9p,fsdev=fsdev0,mount_tag=tag0 \ > -fsdev local,path=/vm/fs,id=fsdev1... \ > -device virtio-9p,fsdev=fsdev1,mount_tag=tag1 \ > -fsdev local,path=/vm/fs,id=fsdev2... \ > -device virtio-9p,fsdev=fsdev2,mount_tag=tag2 > > and /etc/fstab in the guest: > > tag0 / 9p nofail,trans=virtio,version=9p2000.L 0 0 > tag1 /shares 9p nofail,trans=virtio,version=9p2000.L 0 0 > tag2 /tmp 9p nofail,trans=virtio,version=9p2000.L 0 0 > > This involves some more work for the user but it doesn't require > any changes in QEMU. So your suggestion is actually: don't fix it. "Some" more work for the user is a quantity of how many guests you are running, multiplied by the nested virtualization levels you might have = potentially a lot of work for admins. > Would this approach solve the issues you've been hitting with Samba ? No, because that completely neglects runtime changes on a higher level (host), plus it completely destroys the fundamental idea about 9p, which is about transparency of the higher level(s). May I ask, do you have concrete reasons why you want to abondon the entire patch set? Because that's what it sounds to me. Best regards, Christian Schoenebeck