Re: [PATCH] spi: bcm2835: do not unregister controller in shutdown handler
From: Jason Gunthorpe <jgg@ziepe.ca>
Date: 2021-10-04 18:37:51
Also in:
linux-integrity, linux-spi, lkml, stable
On Mon, Oct 04, 2021 at 08:30:52PM +0200, Lino Sanfilippo wrote:
On 04.10.21 at 17:44, Jason Gunthorpe wrote:quoted
Well, that is up to the driver implementing this. It looks like device shutdown is called before the userspace is all nuked so yes, concurrency with userspace is a possible concern here.So the TPM driver has to handle remove() after shutdown() anyway, right? Because even if not caused by the BCM2835 drivers controller unregistration something else could unload the module and the problem (NULL pointer access) would be the same.
Technically yes, remove shouldn't crash in this ordering - but it should be difficult for remove to be called after shutdown in any normal system. Jason _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel