Re: [PATCH v10 8/9] platform/chrome: Protect cros_ec_device lifecycle with revocable

From: Tzung-Bi Shih

Date: Fri May 15 2026 - 04:34:16 EST


On Thu, May 14, 2026 at 01:02:14PM -0300, Jason Gunthorpe wrote:
> On Thu, May 14, 2026 at 03:33:55AM +0000, Tzung-Bi Shih wrote:
>
> > > Given you say this is such a bug I think you really should be sending
> > > a series that is patches 5 through 7 from the other series and a
> > > simple rwsem instead of misc_deregister_sync() to deal with this bug
> > > ASAP. No need to complicate a simple bug fix in a driver with all
> > > these core changes.
> >
> > Apologies for missing this suggestion.
> >
> > For "patches 5 through 7 from the other series" I guess you're referring:
> > - https://lore.kernel.org/all/20260427134659.95181-6-tzungbi@xxxxxxxxxx
> > - https://lore.kernel.org/all/20260427134659.95181-7-tzungbi@xxxxxxxxxx
> > - https://lore.kernel.org/all/20260427134659.95181-8-tzungbi@xxxxxxxxxx
>
> Yes
>
> > Could you provide a bit more detail on the rwsem approach? I'm not
> > entirely clear on what data or operations the rwsem would be protecting.
>
> Just put a rwsem, or even scru, inside the driver's fops.
>
> You can refactor that out to a misc or revocable later.

I see. Thank you for your suggestion. I will explore it and send out a
new version.