Re: [PATCH v1 1/1] drivers: base: Fix NULL pointer exception in __platform_driver_probe()

From: Greg KH
Date: Wed Apr 29 2020 - 03:47:17 EST


On Tue, Apr 28, 2020 at 12:24:05PM -0700, Kuppuswamy, Sathyanarayanan wrote:
> Hi Greg,
>
> On 4/28/20 12:03 PM, Greg KH wrote:
> > On Wed, Apr 08, 2020 at 02:40:03PM -0700, sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx wrote:
> > > From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> > >
> > > If platform bus driver registration is failed then,
> >
> > How is your platform driver registration failing? What caused that, is
> > it an in-kernel problem with something? How can it be triggered?
> In my case I triggered it intentionally. For one of our internal
> project we want to strictly control the number of drivers/devices
> allowed in kernel. To verify the feasibility of adding above support,
> I intentionally failed few bus drivers and checked the behavior. In
> one of those tests I hence came across the mentioned issue.
>
> In any case, platform bus driver registration failure is a valid case
> right ? Any issue we notice when this happens needs to be handled right?

That's fine, I just need to know if this is something that someone can
actually trigger today, and needs to be fixed up, or if this is just a
"hardening for when a driver author does something foolish" type of a
case.

It seems to be the "don't do foolish things" to me, so it's a much lower
priority as we can always fix foolish drivers because we have the source
to them :)

thanks,

greg k-h