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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 15607CA9EAF for ; Thu, 24 Oct 2019 13:17:28 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 D42212084C for ; Thu, 24 Oct 2019 13:17:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="F6icXuxV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D42212084C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:42300 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNczW-0005nb-Dg for qemu-devel@archiver.kernel.org; Thu, 24 Oct 2019 09:17:26 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50394) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNcdJ-0004Fq-Go for qemu-devel@nongnu.org; Thu, 24 Oct 2019 08:54:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iNcdG-00071M-Ps for qemu-devel@nongnu.org; Thu, 24 Oct 2019 08:54:28 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:21417 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iNcdG-000716-LP for qemu-devel@nongnu.org; Thu, 24 Oct 2019 08:54:26 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1571921666; 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=59X5Zte38Cgzy7JMHUGFe9KOmVyhJUTAXgKbgIdm69k=; b=F6icXuxVIcgnr60PoyC37/dxb87Mf3tniED0ltkgJNhbQGGo2u0r9Wgf3420kxg7ffW9d4 OvbSEbtCGrDf2ilMVTs6O6BUcR0bEnNHJkKr9Yc/BnuBJmCT2kZLZNmIUFBavXPI4kjdEd /G3l0CR5NxYRuxpEDSD8jDN3415aad8= 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-8-dXN9-o_uONivsNoRgWttMw-1; Thu, 24 Oct 2019 08:54:24 -0400 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 17ACE5E4; Thu, 24 Oct 2019 12:54:23 +0000 (UTC) Received: from work-vm (ovpn-117-248.ams2.redhat.com [10.36.117.248]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7EAA01001B33; Thu, 24 Oct 2019 12:54:12 +0000 (UTC) Date: Thu, 24 Oct 2019 13:54:10 +0100 From: "Dr. David Alan Gilbert" To: "Michael S. Tsirkin" Subject: Re: [PATCH 00/30] virtiofs daemon (base) Message-ID: <20191024125410.GE2877@work-vm> References: <20191021105832.36574-1-dgilbert@redhat.com> <157166664425.24734.3489596262271351160@37313f22b938> <20191021143357.GB5837@work-vm> <20191024065826-mutt-send-email-mst@kernel.org> <20191024110708.GI3700@redhat.com> <20191024111439.GD2877@work-vm> <20191024071738-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 In-Reply-To: <20191024071738-mutt-send-email-mst@kernel.org> User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-MC-Unique: dXN9-o_uONivsNoRgWttMw-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 205.139.110.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= , qemu-devel@nongnu.org, piaojun@huawei.com, stefanha@redhat.com, marcandre.lureau@redhat.com, eguan@linux.alibaba.com, vgoyal@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Michael S. Tsirkin (mst@redhat.com) wrote: > On Thu, Oct 24, 2019 at 12:14:39PM +0100, Dr. David Alan Gilbert wrote: > > * Daniel P. Berrang=E9 (berrange@redhat.com) wrote: > > > On Thu, Oct 24, 2019 at 06:59:33AM -0400, Michael S. Tsirkin wrote: > > > > On Mon, Oct 21, 2019 at 03:33:57PM +0100, Dr. David Alan Gilbert wr= ote: > > > > > * no-reply@patchew.org (no-reply@patchew.org) wrote: > > > > > > Patchew URL: https://patchew.org/QEMU/20191021105832.36574-1-dg= ilbert@redhat.com/ > > > > > >=20 > > > > > >=20 > > > > > >=20 > > > > > > Hi, > > > > > >=20 > > > > > > This series seems to have some coding style problems. See outpu= t below for > > > > > > more information: > > > > > >=20 > > > > > > Subject: [PATCH 00/30] virtiofs daemon (base) > > > > > > Type: series > > > > > > Message-id: 20191021105832.36574-1-dgilbert@redhat.com > > > > > >=20 > > > > > > =3D=3D=3D TEST SCRIPT BEGIN =3D=3D=3D > > > > > > #!/bin/bash > > > > > > git rev-parse base > /dev/null || exit 0 > > > > > > git config --local diff.renamelimit 0 > > > > > > git config --local diff.renames True > > > > > > git config --local diff.algorithm histogram > > > > > > ./scripts/checkpatch.pl --mailback base.. > > > > >=20 > > > > > Expecting checkpatch to be broken here; most of the files > > > > > follow FUSE's formatting. > > > > >=20 > > > > > Dave > > > >=20 > > > > I wonder what do others think about this. > > > > One problem with such inconsistencies is that people tend to copy c= ode > > > > around, which tends to result in a mess. > > >=20 > > > IIUC, most of this code is simpy copied as-is from the fuse or linux > > > git repos. I'm wondering what the intention is for it long term ? > > >=20 > > > For header files, I would have expected us to be able to compile agai= nst > > > the -devel package provided by the kernel or fuse packages. I can > > > understand if we want to import the headers if the VSOCK additions to > > > them are not yet widely available in distros though. If this is the c= ase > > > we should put a time limit on how long we'd keep these copied headers > > > around for before dropping them. It would be fine to violate QEMU cod= ing > > > style in this case as its not code QEMU would "maintain" long term - = just > > > a read-only import. > >=20 > > The headers are really two types; one are external definitions, the > > other are internal parts of libfuse. I'd expect to keep the internal > > parts long term; teh external parts hmm; where would we pull them in > > externally from? > >=20 > > > The source files though, we appear to then be modifying locally, whic= h > > > suggests they'll live in our repo forever. In this case I'd expect to > > > have compliance with QEMU coding standards. > >=20 > > OK. > >=20 > > > I'm surprised we need to copy so much in from fuse though. Is there a > > > case to be made for fuse to provide a library of APIs for people who > > > are building fuse daemons to link against, instead of copy & fork ? > >=20 > > libfuse *is* such a library; but it preserves ABI compliance; it's > > intention is to be used to build filesystem implementations on top of - > > and that's got a fairly good separation; however changing the fuse > > transport, and security models is much more invasive than it was > > designed for. > >=20 > > Dave >=20 >=20 > I guess you did try to propose adding the functionality to the libfuse > maintainer and got rejected? If not it's worth asking. I looked at it; we started off thinking we'd merge much of it up there - but there's at least two problems: a) Our libvhost-user isn't a separable library either - so we'd need to copy it into libfuse which is just as big a problem. b) It's not additional interfaces, it's changes to existing APIs that break A*B*I compatibility that are very hard to avoid when you're changing the transport. Also, we're not just changing the transport - if you look at the security patchset we're inverting the security model and there's a bunch of threading changes that you haven't got yet. Dave >=20 >=20 > > > Regards, > > > Daniel > > > --=20 > > > |: https://berrange.com -o- https://www.flickr.com/photos/dbe= rrange :| > > > |: https://libvirt.org -o- https://fstop138.berran= ge.com :| > > > |: https://entangle-photo.org -o- https://www.instagram.com/dbe= rrange :| > > -- > > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK