Peter Xu <pet...@redhat.com> writes: > It's not straightforward to see why src QEMU needs to sync multifd during > setup() phase. After all, there's no page queued at that point. > > For old QEMUs, there's a solid reason: EOS requires it to work. While it's > clueless on the new QEMUs which do not take EOS message as sync requests. > > One will figure that out only when this is conditionally removed. In fact, > the author did try it out. Logically we could still avoid doing this on > new machine types, however that needs a separate compat field and that can > be an overkill in some trivial overhead in setup() phase. > > Let's instead document it completely, to avoid someone else tries this > again and do the debug one more time, or anyone confused on why this ever > existed. > > Signed-off-by: Peter Xu <pet...@redhat.com>
Reviewed-by: Fabiano Rosas <faro...@suse.de>
