Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757531AbbKFQTA (ORCPT ); Fri, 6 Nov 2015 11:19:00 -0500 Received: from foss.arm.com ([217.140.101.70]:42853 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757386AbbKFQS7 (ORCPT ); Fri, 6 Nov 2015 11:18:59 -0500 Date: Fri, 6 Nov 2015 16:19:00 +0000 From: Will Deacon To: Catalin Marinas Cc: Yang Shi , linaro-kernel@lists.linaro.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] arm64: remove redundant FRAME_POINTER kconfig option Message-ID: <20151106161859.GS6087@arm.com> References: <1446658671-16238-1-git-send-email-yang.shi@linaro.org> <20151106123008.GK6087@arm.com> <20151106161214.GY7637@e104818-lin.cambridge.arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151106161214.GY7637@e104818-lin.cambridge.arm.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1246 Lines: 27 On Fri, Nov 06, 2015 at 04:12:14PM +0000, Catalin Marinas wrote: > On Fri, Nov 06, 2015 at 12:30:09PM +0000, Will Deacon wrote: > > On Wed, Nov 04, 2015 at 09:37:51AM -0800, Yang Shi wrote: > > > FRAME_POINTER is defined in lib/Kconfig.debug, it is unnecessary to redefine > > > it in arch/arm64/Kconfig.debug. > > > > It might be worth noting that this adds a dependency on DEBUG_KERNEL > > for building with frame pointers. I'm ok with that (it appears to be > > enabled in defconfig and follows the vast majority of other archs) but > > it is a change in behaviour. > > We shouldn't have the dependency on DEBUG_KERNEL since we select > ARCH_WANT_FRAME_POINTERS on arm64. However, the patch would allow one to > disable FRAME_POINTERS (not sure it has any effect on the aarch64 gcc > though). Ah yes, you're right about DEBUG_KERNEL. I completely misread the brackets and the left-associativity of &&/|| works out. I still think Rutland has a valid point wrt junk frame pointers, though. Will -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/