Re: [PATCH v8 3/7] migration: enable multifd and postcopy together

[Fabiano Rosas <farosas@suse.de>]

Prasad Pandit <ppandit@redhat.com> writes:

> On Mon, 31 Mar 2025 at 20:57, Fabiano Rosas <farosas@suse.de> wrote:
>> > --- a/migration/ram.c
>> > +++ b/migration/ram.c
>> > @@ -1297,7 +1297,7 @@ static int find_dirty_block(RAMState *rs, PageSearchStatus *pss)
>> >          pss->page = 0;
>> >          pss->block = QLIST_NEXT_RCU(pss->block, next);
>> >          if (!pss->block) {
>> > -            if (multifd_ram_sync_per_round()) {
>> > +            if (multifd_ram_sync_per_round() && !migration_in_postcopy()) {
>>
>> I'd rather not put this check here. multifd_ram_flush_and_sync() will
>> already return 0 if in postcopy.
>
> * IIRC, without it migration did not finish or was crashing. I don't
> recall if it was on Fedora or RHEL systems.
>

Maybe you hit the issue I reported? Let's not duplicate the in_postcopy
check unless it makes logical sense. If it crashes, we must figure out
why.

> Thank you.
> ---
>   - Prasad