From patchwork Fri Feb 14 21:21:29 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andi Kleen X-Patchwork-Id: 3654621 Return-Path: X-Original-To: patchwork-linux-kbuild@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 16896BF13A for ; Fri, 14 Feb 2014 21:29:22 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4B8CC201CE for ; Fri, 14 Feb 2014 21:29:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 61799201DE for ; Fri, 14 Feb 2014 21:29:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753186AbaBNVW2 (ORCPT ); Fri, 14 Feb 2014 16:22:28 -0500 Received: from mga11.intel.com ([192.55.52.93]:38604 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752583AbaBNVW1 (ORCPT ); Fri, 14 Feb 2014 16:22:27 -0500 Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga102.fm.intel.com with ESMTP; 14 Feb 2014 13:22:26 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.95,847,1384329600"; d="scan'208";a="481803145" Received: from laut.jf.intel.com (HELO localhost) ([10.23.232.94]) by fmsmga002.fm.intel.com with ESMTP; 14 Feb 2014 13:22:25 -0800 Received: by localhost (Postfix, from userid 1000) id 0AB38124B08; Fri, 14 Feb 2014 22:21:46 +0100 (CET) From: Andi Kleen To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, linux-kbuild@vger.kernel.org, mmarek@suse.cz, Joe Mario , rusty@rustcorp.com.au, Andi Kleen Subject: [PATCH 05/19] lto: Handle LTO common symbols in module loader Date: Fri, 14 Feb 2014 22:21:29 +0100 Message-Id: <1392412903-25733-6-git-send-email-andi@firstfloor.org> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1392412903-25733-1-git-send-email-andi@firstfloor.org> References: <1392412903-25733-1-git-send-email-andi@firstfloor.org> Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Joe Mario Here is the workaround I made for having the kernel not reject modules built with -flto. The clean solution would be to get the compiler to not emit the symbol. Or if it has to emit the symbol, then emit it as initialized data but put it into a comdat/linkonce section. Minor tweaks by AK over Joe's patch. Cc: rusty@rustcorp.com.au Signed-off-by: Andi Kleen --- kernel/module.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/module.c b/kernel/module.c index d24fcf2..b99e801 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1948,6 +1948,10 @@ static int simplify_symbols(struct module *mod, const struct load_info *info) switch (sym[i].st_shndx) { case SHN_COMMON: + /* Ignore common symbols */ + if (!strncmp(name, "__gnu_lto", 9)) + break; + /* We compiled with -fno-common. These are not supposed to happen. */ pr_debug("Common symbol: %s\n", name);