Re: [Qemu-devel] [PATCH] migration: invalidate cache before source start

[Vladimir Sementsov-Ogievskiy]

15.06.2018 15:06, Dr. David Alan Gilbert wrote:
> * Vladimir Sementsov-Ogievskiy (address@hidden) wrote:
> > Invalidate cache before source start in case of failed migration.
> >
> > Signed-off-by: Vladimir Sementsov-Ogievskiy <address@hidden>
> Why doesn't the code at the bottom of migration_completion,
> fail_invalidate:   and the code in migrate_fd_cancel   handle this?
>
> What case did you see it in that those didn't handle?
> (Also I guess it probably should set s->block_inactive = false)

on source I see:

address@hidden:migrate_set_state new state 7
address@hidden:migration_thread_file_err
address@hidden:migration_thread_after_loop

so, we are leaving loop on
        if (qemu_file_get_error(s->to_dst_file)) {
            migrate_set_state(&s->state, current_active_state,
MIGRATION_STATUS_FAILED);
trace_migration_thread_file_err();
break;
        }

and skip migration_completion()


> Dave
>
> > ---
> >
> >   migration/migration.c | 9 ++++++++-
> >   1 file changed, 8 insertions(+), 1 deletion(-)
> >
> > diff --git a/migration/migration.c b/migration/migration.c
> > index 1e99ec9b7e..8f39e0dc02 100644
> > --- a/migration/migration.c
> > +++ b/migration/migration.c
> > @@ -2806,7 +2806,14 @@ static void migration_iteration_finish(MigrationState *s)
> >       case MIGRATION_STATUS_FAILED:
> >       case MIGRATION_STATUS_CANCELLED:
> >           if (s->vm_was_running) {
> > -            vm_start();
> > +            Error *local_err = NULL;
> > +            bdrv_invalidate_cache_all(&local_err);
> > +            if (local_err) {
> > +                error_reportf_err(local_err, "Can't invalidate disks before "
> > +                                  "source vm start");
> > +            } else {
> > +                vm_start();
> > +            }
> >           } else {
> >               if (runstate_check(RUN_STATE_FINISH_MIGRATE)) {
> >                   runstate_set(RUN_STATE_POSTMIGRATE);
> > --
> > 2.11.1
> --
> Dr. David Alan Gilbert / address@hidden / Manchester, UK


--
Best regards,
Vladimir