Re: [Qemu-devel] [PATCH 09/17] migration: Start of multiple fd work

[Daniel P. Berrange]

On Wed, Feb 15, 2017 at 02:46:15PM +0000, Dr. David Alan Gilbert wrote:
> * Daniel P. Berrange (address@hidden) wrote:
> > On Mon, Jan 23, 2017 at 10:32:13PM +0100, Juan Quintela wrote:
> > > We create new channels for each new thread created. We only send through
> > > them a character to be sure that we are creating the channels in the
> > > right order.
> > > 
> > > Note: Reference count/freeing of channels is not done
> > > 
> > > Signed-off-by: Juan Quintela <address@hidden>
> > > ---
> > >  include/migration/migration.h |  6 +++++
> > >  migration/ram.c               | 45 +++++++++++++++++++++++++++++++++-
> > >  migration/socket.c            | 56 
> > > +++++++++++++++++++++++++++++++++++++++++--
> > 
> > BTW, right now libvirt never uses QEMU's tcp: protocol - it does everything
> > with the fd: protocol.  So either we need multi-fd support for fd: protocol,
> > or libvirt needs to switch to use tcp:
> 
> I thought using fd was safer than tcp: because of the race when something else
> could listen on the proposed port on the incoming side between the point of 
> libvirt
> picking the port number and qemu starting.

Hmm, good point.

> > In fact, having said that, we're going to have to switch to use  the tcp:
> > protocol anyway in order to support TLS, so this is just another good
> > reason for the switch.
> 
> I thought you had a way of allowing fd to work for TLS?

Oh yes, I forgot that I made that work :-)

Regards,
Daniel
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