Re: [Xen-devel] [GIT PULL] xen: features and fixes for 4.8-rc0

Rafael J. Wysocki
2016-07-27T23:41:50Z

On Wednesday, July 27, 2016 04:18:32 PM Linus Torvalds wrote:
> On Wed, Jul 27, 2016 at 4:09 PM, Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
> >
> > The STAO definition document:
> >
> > http://wiki.xenproject.org/mediawiki/images/0/02/Status-override-table.pdf
> >
> > requires as to "operate as if that device does not exist", quite literally.
>
> Well, first off, documentation is one thing, actually changing
> behavior is something entirely different.
>
> Theory and practice are *not* the same.

Well, the STAO thing is totally new, so we have the documentation only ATM.

> The other worry I have is that I'd be happier if it's still visible in
> /sys/bus/acpi/ etc. Again, it's one thing to not react to it
> programmatically, and another thing entirely to actually hide the
> information from the rest of the system.
>
> If I read that patch right, it will be hidden from sysfs too. But
> Maybe I'm mistaken.

You're right.

Avoiding to enumerate it entirely is somewhat simpler, because it allows
us to avoid some special casing in a few places IIRC.

I guess we can ask the author of the commit in question to come up with a
patch to unhide that device and we'll see how that looks like.

Thanks,
Rafael