Re: [PATCH 0/3] Revert "revocable: Revocable resource management"

From: Laurent Pinchart

Date: Wed Jan 28 2026 - 20:09:56 EST


On Sun, Jan 25, 2026 at 03:07:41PM +0100, Danilo Krummrich wrote:
> On Sun Jan 25, 2026 at 2:22 PM CET, Laurent Pinchart wrote:
> > It's the wrong solution for most cases, if not all. It will spread in drivers
> > and then become another big piece of technical debt we'll wish we had never
> > merged.
>
> It is a matter of how the revocable pattern is adopted. I.e. I don't think
> drivers should create instances of revocable (device) resources by themselves.
> Instead, I think it should be up to the corresponding subsystems to adopt the
> pattern in the way necessary and make it accessible to drivers instead.
>
> > We know what the right solution to the cdev race is
>
> So, what is it? Assuming that this is what you are referring to, how do you
> prevent accesses to (potentially freed) device resources after the bus device
> has been unbound from the driver for subsystems that may still call back into
> the driver after device unbind?

I've answered this question in another e-mail in this thread, see
https://lore.kernel.org/all/20260129010822.GA3310904@killaraus/

--
Regards,

Laurent Pinchart