From: Calvin Walton Subject: Re: [PATCH 2/3] lib: improve the performance of memcpy and memmove of the general version Date: Sat, 04 Sep 2010 08:59:02 -0400 Message-ID: <1283605142.9039.4.camel@ayu> References: <4C7E2CAC.6080102@cn.fujitsu.com> <82mxrzrsvq.fsf@mid.bfk.de> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: miaox@cn.fujitsu.com, Ingo Molnar , Andrew Morton , Chris Mason , Theodore Ts'o , Andreas Dilger , Linux Kernel , Linux Btrfs , Linux Ext4 To: Florian Weimer Return-path: Received: from mail-iw0-f174.google.com ([209.85.214.174]:59708 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752709Ab0IDM7G (ORCPT ); Sat, 4 Sep 2010 08:59:06 -0400 In-Reply-To: <82mxrzrsvq.fsf@mid.bfk.de> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Fri, 2010-09-03 at 11:03 +0000, Florian Weimer wrote: > * Miao Xie: > > > EXPORT_SYMBOL(memcpy); > > I think you need to change that to EXPORT_SYMBOL_GPL, because the code > is now licensed under the GPL, and not the GPL plus kernel exceptions > (whatever they are, but they undoubtly exist), unlike the original > implementation. I wouldn't think so - the intent of EXPORT_SYMBOL_GPL is to mark symbols that make it obvious that a module was derived from the Linux kernel, as opposed to some sort of generic driver that was just ported to a new interface. (It's not foolproof, it's more of a warning to developers.) If you think of it this way, memcpy is a function defined in the C standard, there's absolutely nothing Linux-specific about using it. Of course, IANAL; and you should probably grab some more opinions on the matter. -- Calvin Walton