Re: [PATCH] random: use correct memory barriers for crng_node_pool

[Herbert Xu]

On Thu, Sep 17, 2020 at 09:58:02AM -0700, Eric Biggers wrote:
>
> smp_load_acquire() is obviously correct, whereas READ_ONCE() is an optimization
> that is difficult to tell whether it's correct or not.  For trivial data
> structures it's "easy" to tell.  But whenever there is a->b where b is an
> internal implementation detail of another kernel subsystem, the use of which
> could involve accesses to global or static data (for example, spin_lock()
> accessing lockdep stuff), a control dependency can slip in.

If we're going to follow this line of reasoning, surely you should
be converting the RCU derference first and foremost, no?

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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