RE: [PATCH v1] migration: fail the cap check if it requires the use of deferred incoming

[Wang, Wei W]

On Friday, May 19, 2023 11:34 PM, Peter Xu wrote:
> > Ah yes indeed it keeps working, because we apply -global bits before
> > setup sockets. Then it's fine by me since that's the only thing I
> > would still like to keep it working. :)
> >
> > If so, can we reword the error message a bit?  Obviously as you said
> > we're not really checking against -defer, but established channels.
> > The problem is if something is established without knowing multifd
> > being there it may not work for multifd or preempt, not strictly about 
> > defer.
> >
> > How about:
> >
> >   "Multifd/Preempt-Mode cannot be modified if incoming channel has
> setup"
> >
> > ?

Yes, I'll reword it a bit.

> 
> We may also want to trap the channel setups on num:
> 
> migrate_params_test_apply():
> 
>     if (params->has_multifd_channels) {
>         dest->multifd_channels = params->multifd_channels;
>     }

Didn’t get this one. What do you want to add to above?