Re: [PATCH v2 5/9] migration: check required subsections are loaded, once

[Peter Xu]

On Tue, Oct 24, 2023 at 12:41:56PM +0200, Juan Quintela wrote:
> > @@ -509,6 +538,13 @@ static int vmstate_subsection_load(QEMUFile *f, const 
> > VMStateDescription *vmsd,
> >          }
> >      }
> >  
> > +    for (i = 0; i < n; i++) {
> > +        if (!visited[i] && vmstate_section_needed(vmsd->subsections[i], 
> > opaque)) {
> > +            trace_vmstate_subsection_load_bad(vmsd->name, 
> > vmsd->subsections[i]->name, "(not visited)");
> > +            return -ENOENT;
> > +        }
> > +    }
> > +
> >      trace_vmstate_subsection_load_good(vmsd->name);
> >      return 0;
> >  }
> 
> This part is the only one where I can see there could be some
> discussion.  So I wil wait to see what other people think.

Previous email:

https://lore.kernel.org/qemu-devel/ZR2P1RbxCfBdYBaQ@x1n/

I still think it is safer to not fail unless justified that we won't hit
surprises in the ->needed().  There are a lot so I assume it's non-trivial
to justify.

We can switch the tracepoint into error_report() in that case, though, as
long as it won't fail the migration.

Thanks,

-- 
Peter Xu