Eric Dumazet [off-list ref] wrote:

This patch is not needed.

You really should read Documentation/RCU , because it looks like you are
quite confused.

When we remove an element from a RCU protected list, all the objects in
the chain are already ready to be caught by rcu readers.

Therefore, no additional memory barrier is needed before doing *np =
n->next;

Please do not add spurious memory barriers. Like atomic operations, we
want all of them being required and possibly documented.

This patch is indeed bogus but accessing an RCU-protected like
this will trigger sparse warnings.  So better make it an
RCU_INIT_POINTER.

Cheers,
-- 
Email: Herbert Xu [off-list ref]
Home Page: http://gondor.apana.org.au/~herbert/
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