[PATCH 1/7] media: aspeed: fix a kernel warning on clk control

[Benjamin Herrenschmidt]

On Thu, 2019-05-09 at 16:51 -0700, Jae Hyun Yoo wrote:
> On 5/9/2019 4:19 PM, Benjamin Herrenschmidt wrote:
> > On Thu, 2019-05-09 at 10:19 -0700, Jae Hyun Yoo wrote:
> > > 
> > > Okay. Probably I need to add one another patch in this series to
> > > address
> > > what you pointed out.
> > > 
> > > I have one question. I reviewed again all bitops in this driver
> > > and
> > > checked that some bitops are protected by a spinlock and some
> > > others
> > > are not. In this case, can I mix use atomic and non-atomic bitops
> > > depend on each bitop's protection state by the spinlock? Or,
> > > would it be
> > > better to change all of them to bool in this case?
> > 
> > No, if some aren't protected by a lock and some are, then they need
> > to
> > remain atomic.
> > 
> > The question then becomes whether the unprotected ones are actually
> > correct or just exposing more races.
> 
> Got it. Not sure yet but I think the protected bitops could be moved
> out
> from the spinlock scope then all bitops could be kept as atomic.

Which is very likely to be extremely racy... (and gratuitously more
costly) :-)

>  I'll
> look at and test this driver code more deeply again, and will submit
> v2
> soon.
> 
> Again, thanks a lot for your review.
> 
> Regards,
> Jae