From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cam-admin0.cambridge.arm.com (cam-admin0.cambridge.arm.com [217.140.96.50]) by ozlabs.org (Postfix) with ESMTP id 5ED89B6F06 for ; Sat, 17 Jul 2010 06:10:03 +1000 (EST) Subject: Re: [RFC PATCH] Kconfig: Enable Kconfig fragments to be used for defconfig From: Catalin Marinas To: Linus Torvalds In-Reply-To: References: <20100713230352.6781.18644.stgit@angua> <1279296221.17878.66.camel@e102109-lin.cambridge.arm.com> <20100716183028.GB26854@n2100.arm.linux.org.uk> Content-Type: text/plain; charset="UTF-8" Date: Fri, 16 Jul 2010 21:09:36 +0100 Message-ID: <1279310976.18579.8.camel@e102109-lin.cambridge.arm.com> Mime-Version: 1.0 Cc: Stephen Rothwell , Daniel Walker , Russell King - ARM Linux , linux-kbuild@vger.kernel.org, Tony Lindgren , Nicolas Pitre , lkml , Uwe =?ISO-8859-1?Q?Kleine-K=F6nig?= , linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, 2010-07-16 at 19:46 +0100, Linus Torvalds wrote: > On Fri, Jul 16, 2010 at 11:40 AM, Nicolas Pitre wrote: > > > > DOH. > > Well, it's possible that the correct approach is a mixture. > > Automatically do the trivial cases (recursive selects, dependencies > that are simple or of the form "x && y" etc), and warn about the cases > that aren't trivial (where "not trivial" may not necessarily be about > fundamentally ambiguous ones, but just "complex enough that I won't > even try"). There is still a risk with this approach when the Kconfig isn't entirely correct. For example, on ARM we have (I pushed a patch already): config CPU_32v6K depends on CPU_V6 config CPU_V7 select CPU_32v6K In this simple approach, we end up selecting CPU_V6 when we only need CPU_V7. There other places like this in the kernel. Of course, kbuild could still warn but if people rely on this feature to select options automatically I suspect they would ignore the warnings. -- Catalin