From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753214AbaBNVW3 (ORCPT ); Fri, 14 Feb 2014 16:22:29 -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 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.95,847,1384329600"; d="scan'208";a="481803145" 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-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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); -- 1.8.5.2