From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olaf Hering <olaf@aepfle.de>
Subject: Re: xenbus and the message of doom
Date: Mon, 2 Jan 2012 18:16:31 +0100
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To: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad@darnok.org>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>, Ian Jackson <Ian.Jackson@eu.citrix.com>, Stefan Bader <stefan.bader@canonical.com>, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
List-Id: xen-devel@lists.xenproject.org

On Tue, Dec 20, Ian Campbell wrote:

> On Tue, 2011-12-20 at 17:29 +0000, Ian Jackson wrote:
> > Konrad Rzeszutek Wilk writes ("Re: [Xen-devel] xenbus and the message of doom"):
> > > Sorry Olaf, have to revert that commit.
> > 
> > I agree.  When we introduced it we weren't aware that most existing
> > implementations of xenstored simply ignore unknown commands rather
> > than replying with an error.  If we had known this we would not have
> > approved Olaf's patch.
> > 
> > That they ignore unknown commands is of course a bug but expecting
> > everyone to update is no good.  Really the best approach would be some
> > kind of discovery mechanism.
> > 
> > Maybe we should have a special path @xenstore/fail_unknown_commands
> > which you could read, or something.  But this time we should try it
> > against old implementations.
> 
> I was sure I'd seen some precedent (and therefore an existing path) for
> this sort of thing at some point but I can't for the life of me find it.


If you could come up with a patch to present xenstored (or other
dom0/toolstack) features, that would be great.

Olaf