On Mon, Feb 27, 2017 at 04:00:15PM +0100, Andrea Arcangeli wrote: > Hello, > > On Mon, Feb 27, 2017 at 11:26:58AM +0000, Dr. David Alan Gilbert wrote: > > * Alexey Perevalov (a.pereva...@samsung.com) wrote: > > > Also if I'm not wrong, commands and pages are transferred over the same > > > socket. Why not to use OOB TCP in this case for commands? > > > > My understanding was that OOB was limited to quite small transfers > > I think the right way is to use a separate FD for the requests, so I'll > > do it after Juan's multifd series. > > OOB would do the trick and we considered it some time ago, but we need > this to work over any network pipe including TLS (out of control of > qemu but setup by libvirt), and OOB being a protocol level TCP > specific feature in the kernel, I don't think there's any way to > access it through TLS APIs abstractions. Plus like David said there > are issues with the size of the transfer.
Correct, there's no facility for handling OOB data when a socket is using TLS. Also note that QEMU might not even have a TCP socket, as when libvirt is tunnelling migration over the libvirtd connection, QEMU will just be given a UNIX socket or even a anoymous pipe. So any use of OOB data is pretty much out of the question. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://entangle-photo.org -o- http://search.cpan.org/~danberr/ :|
