Re: [PATCH v7 0/3] drivers/base: Introduce revocable

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

On Fri, Jan 16, 2026 at 04:17:29PM +0100, Greg KH wrote:
> On Fri, Jan 16, 2026 at 08:02:32AM +0000, Tzung-Bi Shih wrote:
> > The series is separated from [1] to show the independency and compare
> > potential use cases easier.  This is the revocable core part.  Use cases
> > are in other series.
> > 
> > The 1st patch introduces the revocable which is an implementation of ideas
> > from the talk [2].
> > 
> > The 2nd and 3rd patches add test cases for revocable in Kunit and selftest.
> > 
> > [1] https://lore.kernel.org/chrome-platform/20251016054204.1523139-1-tzungbi@kernel.org
> > [2] https://lpc.events/event/17/contributions/1627/
> > 
> > v7:
> > - Rebase onto next-20260115.
> 
> Thanks for sticking with this, I've queued this up in the driver-core
> testing branch for now, thanks!

I'd like to see this being successfully used before we merge it. There's
now one patch series for the GPIO subsystem, which I think is a very
good test case. Bartosz is already reviewing it, and there's a
performance issue that needs to be investigated and addressed.

As discussed during LPC, the UAF issue in the CrOS EC that this series
was initially supposed to fix is best solved with reference counting and
refactoring of the CrOS EC driver framework. The revocable mechanism
isn't the right solution for races between device removal and userspace
access.

-- 
Regards,

Laurent Pinchart