Re: [Qemu-devel] Patch to improve handling of server sockets

[Daniel P. Berrange]

On Wed, May 05, 2010 at 10:53:00AM +0200, Gerd Hoffmann wrote:
>   Hi,
> 
> >>When going for multiple listening sockets in qemu we have to figure
> >>how we'll handle this in a number of places as there is no single
> >>listening address any more.
> >
> >Well, that's what my patch is about.
> 
> Sure.
> 
> >Did you take a look at it?
> 
> Briefly, yes.  Overall it looks sensible to me.  Devil is in the details 
> though, see below.
> 
> Noticed that it probably should get a few helper functions to handle 
> FdLists to avoid the quite simliar open-coded loop-over-all-fds loops 
> all over the place.
> 
> >>Reporting the vnc server address in QMP is one.
> >
> >Not sure what QMP is (this was the first time I looked at QEMU's
> >internals),
> 
> You'll run into qmp for sure when forward-porting the patches to the 
> latest qemu bits.  It is the machine-readable version of the monitor 
> protocol (in qemu 0.12+).
> 
> >but I think my patch only leaves one place TODO where I
> >chose to report only the first address for now, but it shouldn't be too
> >hard to fix that as well.
> 
> Yea.  I've noticed that TODO ;)
> 
> >BTW, in some places I circumvented the need for reporting multiple
> >addresses by simply reporting the name that was passed to QEMU instead.
> 
> This is one of the issues which needs to be addressed somehow.
> 
> First I think qemu should be self-consistent here, i.e. either report 
> the (single) name or the list of addressed everythere.
> 
> Second we have to care about the current users (especially libvirt). 
> Today qemu usually reports the address I think.  Thus I tend to stick to 
> addresses to keep them happy.

>From a libvirt POV the only place we use the address is in the graphics
notification event(s). For the event we know which specific address out 
of the list to report - the one we just did accept() on. libvirt does not 
use the 'info vnc' or 'query-vnc' output at all, so whether that reports 
IP address of hostname doesn't matter to us. It is probably easiest to 
just make it report the same info that was provided on the CLI to -vnc 


Regards,
Daniel
-- 
|: Red Hat, Engineering, London    -o-   http://people.redhat.com/berrange/ :|
|: http://libvirt.org -o- http://virt-manager.org -o- http://deltacloud.org :|
|: http://autobuild.org        -o-         http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505  -o-   F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|