Re: [PATCH v2 10/11] gpiolib: add new ioctl() for monitoring changes in line info

[Andy Shevchenko <andy.shevchenko@xxxxxxxxx>]

On Thu, Dec 5, 2019 at 11:42 AM Bartosz Golaszewski
<bgolaszewski@xxxxxxxxxxxx> wrote:
> śr., 4 gru 2019 o 23:34 Andy Shevchenko <andy.shevchenko@xxxxxxxxx> napisał(a):
> > On Wed, Dec 4, 2019 at 6:03 PM Bartosz Golaszewski <brgl@xxxxxxxx> wrote:

> > > +struct gpioline_info_changed {
> > > +       __u64 timestamp;
> > > +       __u32 event_type;
> > > +       struct gpioline_info info;
> > > +       __u32 padding[4]; /* for future use */
> > > +};
> >
> > Has this been tested against 64-bit kernel / 32-bit userspace case?
> >
>
> No. Since this is a new thing - do you think it's possible to simply
> arrange the fields or add padding such that the problem doesn't even
> appear in the first place?

Yes. this can be done, though be careful about potential endianess
issues (the ABI must be tested on BE as well).

So, the test cases, I can imagine of, should include (k - kernel, u - user):
- 64k-64u: LE and BE
- 64k-32u: LE and BE
- 32k-32u: LE and BE

-- 
With Best Regards,
Andy Shevchenko