Re: suspicious RCU usage in security/selinux/netnode.c

From: Paul Moore
Date: Tue May 15 2012 - 14:35:41 EST


On Tue, May 15, 2012 at 11:37 AM, Paul E. McKenney
<paulmck@xxxxxxxxxxxxxxxxxx> wrote:
> Here you go:
>
> o       rcu_dereference_check() is for code shared between readers and
>        writers, so that it might be protected by either rcu_read_lock()
>        or some lock.
>
> o       rcu_dereference_protected() is for code that is only used by
>        updaters and never by readers.  So rcu_dereference_protected()
>        is (slightly) lighter weight than rcu_dereference_check()
>        because it does not need to protect against concurrent
>        updates.

Perfect, thank you. Looks like rcu_dereference_protected() is the
right choice here. Patch coming tomorrow if not later today.

--
paul moore
www.paul-moore.com
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