From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S970620AbeCSS5i (ORCPT ); Mon, 19 Mar 2018 14:57:38 -0400 Received: from mail-pg0-f67.google.com ([74.125.83.67]:46760 "EHLO mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965820AbeCSS5d (ORCPT ); Mon, 19 Mar 2018 14:57:33 -0400 X-Google-Smtp-Source: AG47ELsxH3fgn5lD6FcKbuMwRmOl7iq1QbVvDGxm2/tb5yI+ABWtBNLwzOrZEsQ/P/nkS8c1tkKBmw== Date: Mon, 19 Mar 2018 11:57:32 -0700 From: Matthias Kaehlcke To: Josh Poimboeuf Cc: Ingo Molnar , linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, peterz@infradead.org, hpa@zytor.com, tglx@linutronix.de Subject: Re: [PATCH 2/2] x86/unwind: Make CONFIG_UNWINDER_ORC=y the default in kconfig for 64-bit Message-ID: <20180319185732.GD37438@google.com> References: <20171013052544.euk7yawni47lhmdq@gmail.com> <9b1237bbe7244ed9cdf8db2dcb1253e37e1c341e.1507924831.git.jpoimboe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <9b1237bbe7244ed9cdf8db2dcb1253e37e1c341e.1507924831.git.jpoimboe@redhat.com> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Josh, El Fri, Oct 13, 2017 at 03:02:01PM -0500 Josh Poimboeuf ha dit: > The ORC unwinder has been stable in testing so far. Give it much wider > testing by making it the default in kconfig for x86_64. It's not yet > supported for 32-bit, so leave frame pointers as the default there. > > Suggested-by: Ingo Molnar > Signed-off-by: Josh Poimboeuf > --- Building an upstream kernel with clang results in plenty of objtool warnings like these: drivers/gpu/drm/i915/dvo_ch7017.o: warning: objtool: ch7017_get_hw_state()+0x80: return with modified stack frame CC drivers/gpu/drm/i915/i915_oa_cflgt2.o ... CC drivers/gpu/drm/i915/intel_lpe_audio.o drivers/gpu/drm/i915/i915_gpu_error.o: warning: objtool: i915_error_printf()+0x6c: return with modified stack frame drivers/gpu/drm/i915/intel_display.o: warning: objtool: pipe_config_err()+0xa6: return with modified stack frame Bisecting shows that the warnings are generated since the ORC unwinder was made the default. Not sure if the issue is on the unwinder side or clang. Any ideas on what could be the problems? Thanks Matthias