"Dr. David Alan Gilbert" <dgilb...@redhat.com> wrote: > * Juan Quintela (quint...@redhat.com) wrote: >> Hi >> >> This series disable hotplug/unplug during migration. Thank to Markus >> for explaining where I had to put the checks. Why? Because during >> migration we will fail if there are changes. For instance, in >> postcopy, if we add a memory region, we would failing. Same for other >> devices if they are not setup exactly the same on destination. >> >> Iidea would be to disable it, andthen enable for the thing that we know that >> work. >> >> This series are on top of my previous RAMState v2 serie. >> >> Commets, please? > > So I think this is probably a good idea, but we should ask Li Zhijian who > added > migration_bitmap_extend if the reason for adding it was because they > needed the hot add to work. > cc'd.
I guess that the problem for them is that the bitmap size was wrong after memory resizing. But I don't know if this has ever worked. > IMHO we really need a 'configuration change mutex' that you can take > to stop any changes in the VM hardware, and that would probably reduce > a lot of the places that hold the BQL for just stopping changes. That was the previous patch. With that one, you can't add/remove hardware during migration. Later, Juan.
