[PATCH v2 0/2] More graceful handling of migration without passt-repair

[David Gibson <david@gibson.dropbear.id.au>]

From Red Hat internal testing we've had some reports that if
attempting to migrate without passt-repair, the failure mode is uglier
than we'd like.  The migration fails, which is somewhat expected, but
we don't correctly roll things back on the source, so it breaks
network there as well.

Handle this more gracefully allowing the migration to proceed in this
case, but allow TCP connections to break

I've now tested this reasonably:
 * I get a clean migration if there are now active flows
 * Migration completes, although connections are broken if
   passt-repair isn't connected
 * Basic test suite (minus perf)

I didn't manage to test with libvirt yet, but I'm pretty convinced the
behaviour should be better than it was.

There are more fragile cases that I'm looking to fix, particularly the
die()s in flow_migrate_source_rollback() and elsewhere, however I ran
into various complications that I didn't manage to sort out today.
I'll continue looking at those tomorrow.  I'm now pretty confident
that those additional fixes won't entirely supersede the changes in
this series, so it should be fine to apply these on their own.

David Gibson (2):
  migrate, flow: Trivially succeed if migrating with no flows
  migrate, flow: Don't attempt to migrate TCP flows without passt-repair

 flow.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

-- 
2.48.1