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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 C9817C2D0DB for ; Mon, 27 Jan 2020 20:20:59 +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 7C26B2467B for ; Mon, 27 Jan 2020 20:20:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="KwPvaJEC" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7C26B2467B 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]:50574 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iwAsU-00017u-LX for qemu-devel@archiver.kernel.org; Mon, 27 Jan 2020 15:20:58 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:37406) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iwAl6-0006y0-GW for qemu-devel@nongnu.org; Mon, 27 Jan 2020 15:13:21 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iwAl4-0006Na-KJ for qemu-devel@nongnu.org; Mon, 27 Jan 2020 15:13:20 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:24714 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iwAl4-0006MM-Eu for qemu-devel@nongnu.org; Mon, 27 Jan 2020 15:13:18 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1580155996; 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=OI42bvDwj/8QG8VM1xYhibU9IoU1+qSNWC/CvCgs5UE=; b=KwPvaJECrWvAh9weBmCHEwvvhu5fIXwQ024pLPZXCWtWSah4sbekdC6YAV2gIpc+aA3G+L 1EyuHLcZ28jx6nvDONIIgJeMP0d0ZrJZCrV6FXkia29zlUI7UYH8XaaP4WciGsM5LwwNi0 OFWG6mO8iX0jM7NwFoPFEn+vaAx4yBU= 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-285-FCC_cIszO9iy1NqEE4rniA-1; Mon, 27 Jan 2020 15:13:14 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9861A477; Mon, 27 Jan 2020 20:13:12 +0000 (UTC) Received: from work-vm (unknown [10.36.118.28]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 62FCE86E0E; Mon, 27 Jan 2020 20:13:02 +0000 (UTC) Date: Mon, 27 Jan 2020 20:12:59 +0000 From: "Dr. David Alan Gilbert" To: Kevin Wolf Subject: Re: Making QEMU easier for management tools and applications Message-ID: <20200127201259.GD3419@work-vm> References: <30664f6e-81da-a6e6-9b20-037fc91290fb@redhat.com> <878slyej29.fsf@dusky.pond.sub.org> <20200123190145.GI657556@redhat.com> <2561a069-ce5f-3c30-b04e-db7cd2fcdc85@redhat.com> <871rrp474i.fsf@dusky.pond.sub.org> <20200124102743.GB824327@redhat.com> <20200124143841.GG4732@dhcp-200-226.str.redhat.com> <87sgk3x2im.fsf@dusky.pond.sub.org> <20200127115606.GA5669@linux.fritz.box> MIME-Version: 1.0 In-Reply-To: <20200127115606.GA5669@linux.fritz.box> User-Agent: Mutt/1.13.0 (2019-11-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-MC-Unique: FCC_cIszO9iy1NqEE4rniA-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com 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] X-Received-From: 207.211.31.81 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: Peter Maydell , Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= , "Denis V. Lunev" , Cleber Rosa , Stefan Hajnoczi , Markus Armbruster , qemu-devel , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau , Paolo Bonzini , Dominik Csapak , John Snow , Eduardo Habkost Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Kevin Wolf (kwolf@redhat.com) wrote: > Am 25.01.2020 um 11:18 hat Markus Armbruster geschrieben: > > Kevin Wolf writes: > >=20 > > > Am 24.01.2020 um 11:27 hat Daniel P. Berrang=E9 geschrieben: > > >> This is finally something I'd consider to be on a par with the > > >> original QEMU syntax, before we added hierarchical data. You > > >> have the minimal possible amount of syntax here. No commas, > > >> no quotes, no curly brackets, etc. > > > > > > This seems to have the same problems as the QEMU command line (how do > > > you distinguish strings from ints, from bools, from null?). > >=20 > > True: YAML provides only string scalars. > >=20 > > TOML provides strings, integers, floats, booleans, and several flavors > > of time. It lacks null. > >=20 > > > It's > > > basically just a pretty-printed version of it with the consequence th= at > > > it needs to be stored in an external file and there is no reasonable = way > > > to keep it in my shell history. > >=20 > > There is a reasonable way to keep it in my file system, though. I find > > that decidedly superior. >=20 > That depends a lot on your use case. >=20 > If you have a long-lived production VM that you always run with the same > configuration, then yes, having a config file for it in the file system > is what you probably want. Currently, for this case, people directly > using QEMU tend to write a script that contains the command line. I > think I do have such scripts somewhere, but their number is very small. >=20 > My common case is short-lived VMs with configurations that change very > often between QEMU invocations. Here the command line is decidedly > superior. I can imagine you could do something similar to gdb's --eval-command option which lets you pass a command to be executed at startup; gdb's syntax is a bit painful but it feels like that could be fixed, e.g. I have: gdb --eval-command=3D'set pagination off' --eval-command=3D'set confirm no'= --eval-command=3D'handle SIGPIPE print pas s nostop' --eval-command=3D'handle SIGBUS print pass nostop' --eval-command= =3Dr --eval-command=3D'thread apply all bt full' --eval-command=3D'info proc mappings' --eval-command=3D'info threads' --ev= al-command=3Dq --args $QEMUTODEBUG "$@" in a script. Dave > Requiring me to create a file in the file system each time and to > remember deleting it after I'm done feels about as convenient as a *nix > shell that doesn't accept parameters for commands on the command line, > but instead requires you to write a one-off script first and then run > that. >=20 > Kevin >=20 >=20 -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK