From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:44748) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R0yWZ-0008BV-Vj for qemu-devel@nongnu.org; Tue, 06 Sep 2011 12:29:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1R0yWU-0006EL-2U for qemu-devel@nongnu.org; Tue, 06 Sep 2011 12:29:23 -0400 Received: from thoth.sbs.de ([192.35.17.2]:28112) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R0yWT-0006E0-Mx for qemu-devel@nongnu.org; Tue, 06 Sep 2011 12:29:18 -0400 Message-ID: <4E664A59.3030203@siemens.com> Date: Tue, 06 Sep 2011 18:29:13 +0200 From: Jan Kiszka MIME-Version: 1.0 References: <20110906144828.GA20834@redhat.com> <4E66402C.2020900@siemens.com> <4E66417E.6040308@codemonkey.ws> <20110906160903.GA21675@redhat.com> In-Reply-To: <20110906160903.GA21675@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 0/6] Device state visualization reloaded List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: Markus Armbruster , Anthony Liguori , qemu-devel , Luiz Capitulino On 2011-09-06 18:09, Michael S. Tsirkin wrote: > On Tue, Sep 06, 2011 at 10:51:26AM -0500, Anthony Liguori wrote: >> On 09/06/2011 10:45 AM, Jan Kiszka wrote: >>> On 2011-09-06 16:48, Michael S. Tsirkin wrote: >>>> I'm afraid that won't be enough to stop people >>>> scripting this command - libvirt accessed >>>> HMP for years. >>>> >>>> On the other hand, no QMP command means e.g. >>>> libvirt users don't get any benefit from this. >>>> >>>> What I think will solve these problems, for both HMP and QMP, >>>> is an explicit 'debug_unstable' or 'debug_unsupported' command that will >>>> expose all kind of debugging functionality making it >>>> very explicit that it's an unsupported debugging utility. >>>> >>>> Proposed syntax: >>>> >>>> debug_unstable >>>> >>>> Example: >>>> >>>> debug_unstable device_show -all >>> >>> For HMP, this would needlessly complicate the user interface, nothing I >>> would support. People scripting things on top of HMP are generally doing >>> this on their own risk and cannot expect output stability. >>> >>> device_show is like info qtree: the output will naturally change as the >>> emulated hardware evolves, information is added/removed, or we simply >>> improve the layout. Recent changes on info network are an example for >>> the latter. >> >> Yeah, I'm not worried about stability. HMP commands that aren't >> exposed as QMP commands are inherently unstable and should not be >> scripted to. > > They are also not accessible when using libvirt, right? > Which means almost all cases I care about: debugging on my laptop > I can easily attach with gdb and inspect state. HMP passthrough or - I bet that's what you rather want - monitor passthrough from gdb. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux