Re: [PATCH for-8.0 3/3] migration: Recover behavior of preempt channel creation for pre-7.2

[Juan Quintela]

Peter Xu <peterx@redhat.com> wrote:
> In 8.0 devel window we reworked preempt channel creation, so that there'll
> be no race condition when the migration channel and preempt channel got
> established in the wrong order in commit 5655aab079.
>
> However no one noticed that the change will also be not compatible with
> older qemus, majorly 7.1/7.2 versions where preempt mode started to be
> supported.
>
> Leverage the same pre-7.2 flag introduced in the previous patch to recover
> the behavior hopefully before 8.0 releases, so we don't break migration
> when we migrate from 8.0 to older qemu binaries.
>
> Fixes: 5655aab079 ("migration: Postpone postcopy preempt channel to be after 
> main")
> Signed-off-by: Peter Xu <peterx@redhat.com>

Reviewed-by: Juan Quintela <quintela@redhat.com>
queued.