Re: [Qemu-devel] [PATCH v3 7/9] fdc: check if media rate is correct before doing any transfer

[Markus Armbruster]

Hervé Poussineau <address@hidden> writes:

> The programmed rate has to be the same as the required rate for the
> floppy format ; if that's not the case, the transfer should abort.
>
> Revalidate floppy after migration, so media_rate field doesn't have
> to be saved/restored.

I'm not at all sure that's a good idea.

The rate is guest state.  It's value depends on the media.  We guess the
media to use for a particular image.  Same thing as for the geometry
(heads, tracks, sectors per track).  We do migrate the geometry, see
vmstate_fdrive.

Why is it a good idea to treat rate differently?

Doesn't your fd_revalidate() in fdc_post_load() clobber the migrated
geometry?