RE: [Xen-devel] yanked share problem

["M.A. Williamson" <maw48@xxxxxxxxx>]

> Yes, that's the desired way in most cases, as long as domain crash event 
> can be notified to xenstore and then watches upon specific node can work 
> for this purpose. Normal shutdown command issued from user can follow 
> this process due to driver code aware to send traffic on xenbus. But 
> abnormal crash may not go to such branch. Maybe we need a heartbeat check 
> between xenstore and hooked domains? ;-)
When a domain dies (for any reason), a VIRQ_DOM_EXC will be sent to dom0, 
telling it that something "exceptional" (like being shutdown, or crashing) 
has happened to a domain. This causes some entity (currently still Xend, 
AFAIK) to go check the state of all the domains - the store will get 
updated appropriately as a result of this.
This should work even for crashes - in the current world, this mechanism 
also ensures it's possible to restart domains, clean up their devices, etc 
if they die unexpectedly.
So watching the store ought to be fine in all cases, so long as dom0 stays 
up (which is another problem ;-)
Cheers,
Mark

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel