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=-19.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=ham 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 B4D9CC43381 for ; Wed, 6 Mar 2019 18:44:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 855152063F for ; Wed, 6 Mar 2019 18:44:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="jA2n9ERj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727748AbfCFSoO (ORCPT ); Wed, 6 Mar 2019 13:44:14 -0500 Received: from mail-pf1-f195.google.com ([209.85.210.195]:37375 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727378AbfCFSoN (ORCPT ); Wed, 6 Mar 2019 13:44:13 -0500 Received: by mail-pf1-f195.google.com with SMTP id s22so9305182pfh.4 for ; Wed, 06 Mar 2019 10:44:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=5Q9JVrQM5g86z//emudDTvqgPCz4G8IKm2xbJJqgFAs=; b=jA2n9ERjAeNYQ4YfUc3qfGQ3ahMZEF4MXXHz/T1/IgjlS/0CvjUUaPhgJXHAIsT/do RuaYSD9mJTKdqjb/PT2zouMF289k4vYYVZdw8btr3dPxVR4qf9YOeiP7MSVkON0P93hi g8GzzkO74wHExyX70+RCv+nHTDr7IdQinsVhhIZAkFU9IVmFkOiddfiFx9T+7e2C+IyA cup6ItcuTo/l1ajNOoYI8Cv2/ViJcoMKQyDVT9ygD6pUNdPA+RJjZwsjL58Qd6srYmmV EV7NA9F/a+VFMUIo9wzLmTsvS5MIijcPa1/BSKb/KaerBi1QwuVsAEO3FU77m989iHEv OLaw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=5Q9JVrQM5g86z//emudDTvqgPCz4G8IKm2xbJJqgFAs=; b=KYOOyGcDQ5zFeNa+8IxlIsk8Dty+19gzqsGim4EziAovDswQGoZSubudYMd1Jq2MPG tXBBKWWdGgLqUAKsFDTtLydIj3wJw5CW1jLnNz35Sm1Mc3hhdN5t7O4YmQN4PeEKcFDU EMefPhsle71mQLReepC1IiPPGZX3CMNnl0qmm+Z2zGkWT/3YXfsyeYiN3r17SViCNMdK cfWYqeqeF6S3JJjy4FRAndkp38hD0ujCl99kYq298Orp4D8UOPHxwu5zckADV9IBA0Cj ojRggJkd04YIgL9CcD6GTxpwdtt6OUMV8ch4Wn+GPSRdLg1l35GCMTGNla5GDhk0EWUy U/zA== X-Gm-Message-State: APjAAAWWFW23eyRtJhG1C0d7IvEK6GMFwk8uglNbtdjUElgjt/aqow2I I94QgtNW7G63HOL95DAEKTpA1eOHvJAPHXZUIB/WHw== X-Google-Smtp-Source: APXvYqzExV9zVNTVE6yf/7E/2CMSjaN/3x6J0E1R2XGjmMF0HI5/BoFfIyFTGTnB79zO5d+5orms2nDy91XnDM6LM2Y= X-Received: by 2002:a17:902:3f81:: with SMTP id a1mr8419549pld.238.1551897852619; Wed, 06 Mar 2019 10:44:12 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Nick Desaulniers Date: Wed, 6 Mar 2019 10:44:01 -0800 Message-ID: Subject: Re: [PATCH] x86/unwind/orc: Fix ORC unwind table alignment To: Josh Poimboeuf Cc: x86@kernel.org, LKML , Peter Zijlstra , Dmitry Golovin , Sedat Dilek Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 6, 2019 at 9:08 AM Josh Poimboeuf wrote: > > The .orc_unwind section is a packed array of 6-byte structs. It's > currently aligned to 6 bytes, which is causing warnings in the LLD > linker. > > Six isn't a power of two, so it's not a valid alignment value. The > actual alignment doesn't matter much because it's an array of packed > structs. An alignment of two is sufficient. In reality it always gets > aligned to four bytes because it comes immediately after the > 4-byte-aligned .orc_unwind_ip section. > > Link: https://github.com/ClangBuiltLinux/linux/issues/218 > Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder") Thanks for the patch Josh, we appreciate it. It looks like ee9f8fce9964 landed in v4.14-rc1. Should we CC stable? > Reported-by: Nick Desaulniers > Reported-by: Dmitry Golovin > Reported-by: Sedat Dilek > Tested-by: Sedat Dilek > Signed-off-by: Josh Poimboeuf > --- > include/asm-generic/vmlinux.lds.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h > index 3d7a6a9c2370..f8f6f04c4453 100644 > --- a/include/asm-generic/vmlinux.lds.h > +++ b/include/asm-generic/vmlinux.lds.h > @@ -733,7 +733,7 @@ > KEEP(*(.orc_unwind_ip)) \ > __stop_orc_unwind_ip = .; \ > } \ > - . = ALIGN(6); \ > + . = ALIGN(2); \ > .orc_unwind : AT(ADDR(.orc_unwind) - LOAD_OFFSET) { \ > __start_orc_unwind = .; \ > KEEP(*(.orc_unwind)) \ > -- > 2.17.2 > -- Thanks, ~Nick Desaulniers