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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 217BDCA9ECB for ; Thu, 31 Oct 2019 13:37:50 +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 DD15920862 for ; Thu, 31 Oct 2019 13:37:49 +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="Xaosgiuy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DD15920862 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]:50148 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iQAe4-0005tq-QZ for qemu-devel@archiver.kernel.org; Thu, 31 Oct 2019 09:37:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39132) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iQAcb-0003eD-GV for qemu-devel@nongnu.org; Thu, 31 Oct 2019 09:36:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iQAcY-0007Aa-Gc for qemu-devel@nongnu.org; Thu, 31 Oct 2019 09:36:15 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:24590 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 1iQAcW-00078n-RN for qemu-devel@nongnu.org; Thu, 31 Oct 2019 09:36:14 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1572528971; 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=HofgZqCvk6WiGZ+EOChwGzwxCdve88vIW2QvyZeY1OM=; b=XaosgiuysnENkdhgXzXeAC/zYgok4HfXZ3nADFTPnlSa18F5zl/PR0a5etOiMyu2Hu4AXf NSGWBAJBRDlRr69u2c8OV+Fl7PR6Bv5Uo5Q7zLYDmiijzKGv9NaWomAiwFhe5H1t3bOXOd zj3K8dN8f+Pzg21uQpOYs4l9rcvGg88= 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-245-UODJJHsmOBW1HFBQVcho7A-1; Thu, 31 Oct 2019 09:36:08 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 31D8D107ACC0; Thu, 31 Oct 2019 13:36:07 +0000 (UTC) Received: from work-vm (ovpn-116-247.ams2.redhat.com [10.36.116.247]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4EFBA19C7F; Thu, 31 Oct 2019 13:35:52 +0000 (UTC) Date: Thu, 31 Oct 2019 13:35:49 +0000 From: "Dr. David Alan Gilbert" To: Han Han Subject: Re: [PATCH] fw_cfg: Allow reboot-timeout=-1 again Message-ID: <20191031133549.GC3128@work-vm> References: <20191025165706.177653-1-dgilbert@redhat.com> <87a79o4jjb.fsf@dusky.pond.sub.org> <20191028134700.GB2961@work-vm> <87lft3sqhf.fsf@dusky.pond.sub.org> <20191029125641.GC16329@work-vm> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: UODJJHsmOBW1HFBQVcho7A-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=WINDOWS-1252 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: 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: Karen Noel , Jaroslav Suchanek , philmd@redhat.com, liq3ea@gmail.com, qemu-devel@nongnu.org, Markus Armbruster , kraxel@redhat.com, lersek@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Han Han (hhan@redhat.com) wrote: > However, another important question is: how can we avoid such undocumente= d > incompatibility appears again? The reboot-timeout one was accidental - it was a documented qemu feature; just no one noticed it when the input check was added. Officially if we actually want to deprecate a feature we should actually follow qemu's deprecation guidelines. > I can show another case caused by such incompatibile change: > https://bugzilla.redhat.com/show_bug.cgi?id=3D1745868#c0 >=20 > For the qemu devices, attributes, values, qmp cmds, qmp cmds arguments us= ed > by libvirt, could we get a way to inform libvirt > that an incompatibile qemu change is coming, please update libvirt code > ASAP to adjust to that change? > Or another way that is more gently: popping up the warning of depreciati= on > instead of dropping it, and then drop it in the version > after next version. Yes that should happen; with deprecated devices it's easier than more subtle features like command line things; I'm not sure how that gets introspected. I thought libvirt already asked qemu for a list of devices, so I'm confused why libvirt didn't spot it before starting the VM in 1745868. Dave >=20 > On Tue, Oct 29, 2019 at 1:59 PM Dr. David Alan Gilbert > wrote: >=20 > > * Markus Armbruster (armbru@redhat.com) wrote: > > > "Dr. David Alan Gilbert" writes: > > > > > > > * Markus Armbruster (armbru@redhat.com) wrote: > > > >> "Dr. David Alan Gilbert (git)" writes: > > > >> > > > >> > From: "Dr. David Alan Gilbert" > > > >> > > > > >> > Commit ee5d0f89de3e53cdb0dc added range checking on reboot-timeo= ut > > > >> > to only allow the range 0..65535; however both qemu and libvirt > > document > > > >> > the special value -1 to mean don't reboot. > > > >> > Allow it again. > > > >> > > > > >> > Fixes: ee5d0f89de3e53cdb0dc ("fw_cfg: Fix -boot reboot-timeout > > error checking") > > > >> > RH bz: https://bugzilla.redhat.com/show_bug.cgi?id=3D1765443 > > > >> > Signed-off-by: Dr. David Alan Gilbert > > > >> > --- > > > >> > hw/nvram/fw_cfg.c | 5 +++-- > > > >> > 1 file changed, 3 insertions(+), 2 deletions(-) > > > >> > > > > >> > diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c > > > >> > index 7dc3ac378e..1a9ec44232 100644 > > > >> > --- a/hw/nvram/fw_cfg.c > > > >> > +++ b/hw/nvram/fw_cfg.c > > > >> > @@ -247,10 +247,11 @@ static void fw_cfg_reboot(FWCfgState *s) > > > >> > > > > >> > if (reboot_timeout) { > > > >> > rt_val =3D qemu_opt_get_number(opts, "reboot-timeout", = -1); > > > >> > + > > > >> > /* validate the input */ > > > >> > - if (rt_val < 0 || rt_val > 0xffff) { > > > >> > + if (rt_val < -1 || rt_val > 0xffff) { > > > >> > error_report("reboot timeout is invalid," > > > >> > - "it should be a value between 0 and > > 65535"); > > > >> > + "it should be a value between -1 and > > 65535"); > > > >> > exit(1); > > > >> > } > > > >> > } > > > >> > > > >> Semantic conflict with "PATCH] qemu-options.hx: Update for > > > >> reboot-timeout parameter", Message-Id: > > > >> <20191015151451.727323-1-hhan@redhat.com>. > > > > > > > > Thanks for spotting that. > > > > I think Han and also submitted patches to review it from libvirt > > > > and it wasn't obvious what to do. (Cc'd Han in). > > > > > > > >> I'm too tired right now to risk an opinion on which one we want. > > > > > > > > As is everyone else ! The problem here is that its documented > > > > as a valid thing to do, and libvirt does it, and you might have > > > > a current XML file that did it. Now I think you could change libvi= rt > > > > to omit the reboot-timeout parameter if it was called with -1. > > > > > > > > So given its a documented thing in both qemu and libvirt xml > > > > if we want to remove it then it sohuld be deprecated properly - but > > it's > > > > already broken. > > > > > > Since commit ee5d0f89d, v4.0.0. > > > > > > If that commit had not made it into a release, we'd certainly treat t= he > > > loss of "-1 means don't reboot" as regression. > > > > > > But it has. We can treat it as a regression anyway. We can also > > > declare "ship has sailed". > > > > > > I'm leaning towads the former. > > > > > > If we restore "-1 means don't reboot", then I don't see a need to > > > deprecate it. Just keep it. > > > > > > What do you think? > > > > That's also my view; especially since the problem seems to be an easy > > fix. > > > > Dave > > > > -- > > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK > > >=20 >=20 > --=20 > Best regards, > ----------------------------------- > Han Han > Quality Engineer > Redhat. >=20 > Email: hhan@redhat.com > Phone: +861065339333 -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK