From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: [PATCH 0/2 V3] fix rename: xenstore not fully updated Date: Tue, 25 Nov 2014 10:51:30 -0500 Message-ID: <20141125155130.GE29886@konrad-lan.dumpdata.com> References: <1416378851-32236-1-git-send-email-cyliu@suse.com> <21612.32360.328456.516321@mariner.uk.xensource.com> <20141119212505.GJ20440@laptop.dumpdata.com> <1416497310.14429.20.camel@citrix.com> <20141121170103.GA8314@laptop.dumpdata.com> <1416924781.32327.23.camel@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1416924781.32327.23.camel@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: wei.liu2@citrix.com, Ian Jackson , Chunyan Liu , xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On Tue, Nov 25, 2014 at 02:13:01PM +0000, Ian Campbell wrote: > On Fri, 2014-11-21 at 12:01 -0500, Konrad Rzeszutek Wilk wrote: > > On Thu, Nov 20, 2014 at 03:28:30PM +0000, Ian Campbell wrote: > > > On Wed, 2014-11-19 at 16:25 -0500, Konrad Rzeszutek Wilk wrote: > > > > On Wed, Nov 19, 2014 at 11:26:32AM +0000, Ian Jackson wrote: > > > > > Hi Konrad, I have another release ack request: > > > > > > > > > > Chunyan Liu writes ("[PATCH 0/2 V3] fix rename: xenstore not fully updated"): > > > > > > Currently libxl__domain_rename only update /local/domain//name, > > > > > > still some places in xenstore are not updated, including: > > > > > > /vm//name and /local/domain/0/backend///.../domain. > > > > > > This patch series updates /vm//name in xenstore, > > > > > > > > > > This ("[PATCH 2/2 V3] fix rename: xenstore not fully updated") is a > > > > > bugfix which I think should go into Xen 4.5. > > > > > > > > > > The risk WITHOUT this patch is that there are out-of-tree tools which > > > > > look here for the domain name and will get confused after it is > > > > > renamed. > > > > > > > > When was this introduced? Did it exist with Xend? > > > > > > Based on: > > > git grep domain\" RELEASE-4.4.0 tools/python/ > > > git grep domain\' RELEASE-4.4.0 tools/python/ > > > it doesn't appear so, but someone with a xend install would be needed to > > > confirm for sure. > > > > > > Given that this has always been wrong for a libxl domain after migration > > > it seems likely to me that noone is looking at this field. > > > > And this is not a regression though. > > > > What I am understanding is that we advertise to out-side toolstack > > users for a couple of releases something which is misleading and wrong. > > ...and also basically useless, there is really no reason to be looking > for the domain's name under a subset of the backend nodes (only vkb, vfb > and console have this key at all). None of the helper function which we > provide do this. > > Also these nodes are not advertised as supported either via > docs/misc/xenstore-paths.markdown or xen/include/public/io/*.h. > > > My fear is that there such toolstack users out there who will > > get their pitchforks out when this shows up. > > > > But perhaps there is a way to mitigate this. Is there another way > > (and can it be in the commit description) to get the proper > > domain name? I presume it is just looking at /local/domain/%d/name ? > > > > As such could this be added: > > > > "The proper way to get the domain name is to get it from > > /local/domain/%d/name instead from this field." > > The proper way is to use libxl_domid_to_name, not to go scrobbling > around in xenstore. We could say this (or both) in the commit message > though if it would help to reassure you. That (both) would most certainly reassure me. Thank you! > > Either way I think it really would be best to take this fix rather than > worrying overly about the infinitesimal possibility that someone might > be using this key. Right, so with the reassurance text added on: Release-Acked-by: Konrad Rzeszutek Wilk > > Ian. >