Re: [PATCH v1 00/17] tee: Use bus callbacks instead of driver callbacks

Uwe Kleine-König
2025-12-17T08:21:45Z

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Hello Sumit,

On Wed, Dec 17, 2025 at 01:25:39PM +0530, Sumit Garg wrote:
> On Tue, Dec 16, 2025 at 12:08:38PM +0100, Uwe Kleine-König wrote:
> > On Tue, Dec 16, 2025 at 01:08:38PM +0530, Sumit Garg wrote:
> > > On Mon, Dec 15, 2025 at 3:02 PM Uwe Kleine-König
> > > <u.kleine-koenig@baylibre.com> wrote:
> > > > - Why does optee_probe() in drivers/tee/optee/smc_abi.c unregister all
> > > > optee devices in its error path (optee_unregister_devices())?
> > >
> > > This is mostly to take care of if any device got registered before the
> > > failure occured. Let me know if you have a better way to address that.
> >
> > Without understanding the tee stuff, I'd say: Don't bother and only undo
> > the things that probe did before the failure.
>
> True, but this is special case where if there is any leftover device
> registered from the TEE implementation then it is likely going to cause
> the corresponding kernel client driver crash.

You are aware that this is racy? So if a driver crashes e.g. after
teedev_close_context() it might happen that it is registered just after
optee_unregister_devices() returns.

Best regards
Uwe

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