From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id 7E7BA6B024D for ; Wed, 21 Jul 2010 11:12:49 -0400 (EDT) Message-ID: <4C470E69.7020900@kernel.org> Date: Wed, 21 Jul 2010 17:12:41 +0200 From: Tejun Heo MIME-Version: 1.0 Subject: Re: Dead Config in mm/percpu.c References: <861vaxjij8.fsf@peer.zerties.org> In-Reply-To: <861vaxjij8.fsf@peer.zerties.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Christian Dietrich Cc: David Howells , Christoph Lameter , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On 07/21/2010 11:22 AM, Christian Dietrich wrote: > Hi all! > > As part of the VAMOS[0] research project at the University of > Erlangen we are looking at multiple integrity errors in linux' > configuration system. > > I've been running a check on the mm/ sourcetree for > config Items not defined in Kconfig and found 1 such case. Sourcecode > blocks depending on these Items are not reachable from a vanilla > kernel -- dead code. I've seen such dead blocks made on purpose > e.g. while integrating new features into the kernel but generally > they're just useless. > > We found, that CONFIG_NEED_PER_CPU_KM is a dead symbol, so it isn't defined > anywhere. Cause of that the percpu_km.c is never included anywhere. Is > this a intended dead symbol, for use in out of tree development, or is > this just an error? Oh, it's new code waiting to be used. It's for cases where SMP is used w/o MMU. IIRC, it was blackfin. Thanks. -- tejun -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org