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From: David Howells <dhowells@redhat.com>
In-Reply-To: <20110807175511.GZ2203@ZenIV.linux.org.uk>
References: <20110807175511.GZ2203@ZenIV.linux.org.uk>
To: Al Viro <viro@ZenIV.linux.org.uk>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: dhowells@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: fix rcu annotations noise in cred.h
Date: Mon, 08 Aug 2011 09:18:29 +0100
Message-ID: <13248.1312791509@redhat.com>
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Al Viro <viro@ZenIV.linux.org.uk> wrote:

>  #define current_cred() \
> -	(current->cred)
> +	(*(__force struct cred **)&current->cred)

No.  You've cast away the const.  Please don't do that.

Paul: isn't there some better way of doing this using an RCU wrapper macro?

	#define current_cred() \
		rcu_dereference_protected(current->cred, 1) 

Perhaps?

David