Re: [Qemu-devel] [PATCH for-4.1? 1/2] stellaris_input: Fix vmstate description of buttons field

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Peter Maydell (peter.maydell@linaro.org) wrote:
> On Thu, 25 Jul 2019 at 18:40, Philippe Mathieu-Daudé <philmd@redhat.com> wrote:
> >
> > On 7/25/19 7:02 PM, Dr. David Alan Gilbert wrote:
> > > * Peter Maydell (peter.maydell@linaro.org) wrote:
> > >> gamepad_state::buttons is a pointer to an array of structs,
> > >> not an array of structs, so should be declared in the vmstate
> > >> with VMSTATE_STRUCT_VARRAY_POINTER_INT32; otherwise we
> > >> corrupt memory on incoming migration.
> > >>
> > >> We bump the vmstate version field as the easiest way to
> > >> deal with the migration break, since migration wouldn't have
> > >> worked reliably before anyway.
> > >>
> > >> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> > >
> > > OK, it would be great to change num_buttons to uint32_t and make that a
> > > UINT32 at some point;  it's hard to press negative buttons.
> >
> > Since the version is incremented, now seems to be a good time.
> 
> ...except this patch is for 4.1 and we've already done rc2,
> so it's not really an ideal time to put in code cleanups...

Don't worry; you can always change the int to a uint later without
bumping the version again.  Unless someone somewhere has a device with
-ve buttons it'll be fine.

Dave

> thanks
> -- PMM
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK