Re: [PATCH 3/3] ps2: migration support for command reply queue

[Gerd Hoffmann]

  Hi,

> this part actually works. .needed is only evaluated on the sending side. For
> the receiving side subsections are optional.  Migration doesn't fail if a
> subsection isn't loaded. Before I sent this patch series one of the
> migration tests was a migration from 6.0.92 to 6.0.92 with one byte in the
> command reply queue and 3 bytes in the scancode queue. The migration didn't
> fail.

Hmm, ok.  If you actually tested it you are probably right.  My memory
tells me ->needed() is evaluated on both sending and receiving side as
the migration data stream does not carry the information whenever a
subsection is present or not.  But maybe my memories are wrong, or
things have changed, I don't follow migration changes that closely.

> > If we can't find something we can add a property simliar to the one
> > for the extended keyboard state.
> 
> What is the best way to add such a compat property? The ps2 keyboard isn't a
> qdev device. I can't just add a property to the device class. Do I have to
> add a property to the i8042 and the pl050 device and propagate the property
> value with the ps2_kbd_init() call to the PS2KbdState?

Yes, I think so.  But double-check the migration thing first, if your
approach works that is the easier way of course.

take care,
  Gerd