[virt-tools-list] [virt-manager PATCH 1/2] Disable domain events with XEN

[Cole Robinson]

On 02/25/2015 03:52 PM, Giuseppe Scrivano wrote:
> "Daniel P. Berrange" <berrange at redhat.com> writes:
> 
>> On Wed, Feb 25, 2015 at 04:34:19PM +0100, Giuseppe Scrivano wrote:
>>> When XEN is used, disable domain events and use polling.
>>>
>>> On RHEL-5.9 virDomainInfo() seems to not report correctly the domain
>>> status when called immediately after the event is received.
>>>
>>> Solves: https://bugzilla.redhat.com/show_bug.cgi?id=1177207
>>
>> I'm not convinced there's a bug in libvirt here.
>>
>> VIR_DOMAIN_NOSTATE has always been considered to be a synonym
>> for VIR_DOMAIN_RUNNING - the Xen hypervisor often shows 'nostate'
>> when guests are running. So isn't the bug simply to make virt-manager
>> treat them as equivalent rather than disabling events like this.
> 
> thanks, in fact it doesn't seem to be the issue.  Only the debugging
> message prints it as VIR_DOMAIN_NOSTATE, while the rest of the code
> considers it as VIR_DOMAIN_RUNNING.  Something else is going on, as
> calling virDomainInfo twice, "fix" the problem, and that is why
> re-enabling polling fix the issue.  I will look more into it.

A long time ago I encountered similar issues with RHEL5 xen, after a domain
state change an info() call could report totally bogus data, basically
everything was zeros IIRC. I think I even patches virt-install to try info() a
few times while we were waiting for the VM to change state after install
completed.

Disabling polling might be kinda drastic, but I'd rather do that than
conditionally call info() twice or something like that.

- Cole