Bug 453743

Summary:	Guest userspace cannot access additional xenbus watch data
Product:	Red Hat Enterprise Linux 5	Reporter:	Ian Campbell <ijc>
Component:	kernel-xen	Assignee:	Xen Maintainance List <xen-maint>
Status:	CLOSED INSUFFICIENT_DATA	QA Contact:	Martin Jenner <mjenner>
Severity:	low	Docs Contact:
Priority:	low
Version:	5.2	CC:	clalance
Target Milestone:	rc
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2009-07-29 09:31:43 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	492568

Description Ian Campbell 2008-07-02 10:08:29 UTC

When a xenbus watch fires the event can contain some additional data as well as
the path which fired and the watch token. This additional data is not passed
through to userspace xenbus clients. This functionality is implemented by
upstream changeset http://xenbits.xensource.com/linux-2.6.18-xen.hg?cs=8523584ffaa3.

All RHEL 4 and RHEL 5 kernels have this problem.

Comment 1 Don Dutile (Red Hat) 2008-07-02 15:49:29 UTC

Please state which/what userspace xenbus clients need the additional information,
and how those clients work or don't work w/o the additional information currently.

Comment 2 Bill Burns 2009-02-13 15:54:37 UTC

Ian, any feedback on the need info request?

Comment 3 Ian Campbell 2009-03-30 17:33:38 UTC

Sorry for not getting back to you sooner.

I have attempted to contact the customer who originally made this request to me to find out what they are doing but with no luck. My impression at the time was that they had a simple message passing layer where you watch a node and when it fires you can get a bit of extra detail in the watch message itself rather than having to go to xenstore again to find out what happened, or something like that...

Since the original impetus seems to have gone as far as I am concerned you are welcome to close this, or to leave it as a low priority wishlist bug.

Comment 5 Chris Lalancette 2009-07-29 09:31:43 UTC

I'm closing this for now, as it doesn't seem relevant at the moment.  If the customer that needs this comes back, we can re-open this or open up a new BZ.

Chris Lalancette