From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 92662C3F2D1 for ; Mon, 2 Mar 2020 12:44:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 71682217F4 for ; Mon, 2 Mar 2020 12:44:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727543AbgCBMos (ORCPT ); Mon, 2 Mar 2020 07:44:48 -0500 Received: from gate.crashing.org ([63.228.1.57]:35158 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726806AbgCBMos (ORCPT ); Mon, 2 Mar 2020 07:44:48 -0500 Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id 022CigGl022511; Mon, 2 Mar 2020 06:44:42 -0600 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id 022Cigx2022509; Mon, 2 Mar 2020 06:44:42 -0600 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Mon, 2 Mar 2020 06:44:42 -0600 From: Segher Boessenkool To: Rasmus Villemoes Cc: LKML , Linux Kbuild mailing list , "linuxppc-dev@lists.ozlabs.org" Subject: Re: eh_frame confusion Message-ID: <20200302124442.GI22482@gate.crashing.org> References: <3b00b45f-74b5-13e3-9a98-c3d6b3bb7286@rasmusvillemoes.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3b00b45f-74b5-13e3-9a98-c3d6b3bb7286@rasmusvillemoes.dk> User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 02, 2020 at 11:56:05AM +0100, Rasmus Villemoes wrote: > I'm building a ppc32 kernel, and noticed that after upgrading from gcc-7 > to gcc-8 all object files now end up having .eh_frame section. Since GCC 8, we enable -fasynchronous-unwind-tables by default for PowerPC. See https://gcc.gnu.org/r259298 . > For > vmlinux, that's not a problem, because they all get discarded in > arch/powerpc/kernel/vmlinux.lds.S . However, they stick around in > modules, which doesn't seem to be useful - given that everything worked > just fine with gcc-7, and I don't see anything in the module loader that > handles .eh_frame. It is useful for debugging. Not many people debug the kernel like this, of course. Segher