From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:57793) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R0ww9-0006k2-IB for qemu-devel@nongnu.org; Tue, 06 Sep 2011 10:47:45 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1R0ww0-0002O9-J4 for qemu-devel@nongnu.org; Tue, 06 Sep 2011 10:47:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41136) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R0ww0-0002O5-8B for qemu-devel@nongnu.org; Tue, 06 Sep 2011 10:47:32 -0400 Date: Tue, 6 Sep 2011 17:48:29 +0300 From: "Michael S. Tsirkin" Message-ID: <20110906144828.GA20834@redhat.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] [PATCH 0/6] Device state visualization reloaded List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: Anthony Liguori , Luiz Capitulino , qemu-devel , Markus Armbruster On Fri, Aug 26, 2011 at 04:48:10PM +0200, Jan Kiszka wrote: > More than one year ago I posted some patches to add a monitor command > callend device_show. The purpose of that command is to dump the state of > some qdev device based on its vmstate. > > To improve the usability of that interface, the previous series also > tried to create a canonical qdev tree path name format and even added > monitor command expansion. That format created quite a few discussions, > and we never came to some conclusion. > > As device_show is still a useful tool for debugging but qdev structuring > and addressing may significantly change in the near future, I decided to > reanimate those patches while avoiding almost any change of the > addressing scheme. The only one I propose is automatic ID assignment for > anonymous devices so that any qdev device is in principle addressable > (e.g. APIC and IO-APIC on x86). > > As back then, device_show remains HMP-only to avoid any stable ABI > issues around QMP. 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 -- MSt