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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 A7D0BC4727E for ; Thu, 1 Oct 2020 21:46:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4AEAB206A2 for ; Thu, 1 Oct 2020 21:46:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601588804; bh=33d+5YpKaZy67awLHISI1I7yC3fnUn3elft+nSUfo70=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=NoanCuAnexQ/e0UV+KY6FeNsbY18V/uwTmJZgzaykOyfFf0xnMpQfsvzqACehDz/Y c5UYAQwdkJ/WGmMoqlLbxvCrFnEZ2hOQwjLtslqVMPNjnMTgmTQ/Z4wUu4kZc+uEZ1 P93RuegyiSOC4ZKorrJBsEhUZqmyVyyIqAhOUWME= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727209AbgJAVqn (ORCPT ); Thu, 1 Oct 2020 17:46:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:36260 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726626AbgJAVqm (ORCPT ); Thu, 1 Oct 2020 17:46:42 -0400 Received: from mail-wr1-f49.google.com (mail-wr1-f49.google.com [209.85.221.49]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4D47920848 for ; Thu, 1 Oct 2020 21:46:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601588802; bh=33d+5YpKaZy67awLHISI1I7yC3fnUn3elft+nSUfo70=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=H8qVwXSLBHBvlySX3bMRCImUzAtdDhMN0M2WVdSC+BhPdVLHB6JaG2lptLG8PzAn1 bHwzTGKFroIJ8Smx3efp1Xh/JSWfn99GH4C0wWPcBvzpei08/4l0xQp+cAViKWFsbD X6FqmJyocQeew0SkmCZs1A0keIyAwJdpc1d5nNLg= Received: by mail-wr1-f49.google.com with SMTP id w5so330798wrp.8 for ; Thu, 01 Oct 2020 14:46:42 -0700 (PDT) X-Gm-Message-State: AOAM533lD5aFjPzAqkfdlEzgdXuKp6dVAsASWSovHwD5pHnx4fO3sCZg tqHr60nS/niAGdTBvAGlmt+yWbss9LJQYUDJbeUYwQ== X-Google-Smtp-Source: ABdhPJxzntZTB8wWJHx/Za84yoWi5C8XrMqY1mtJhANu5XAszOcYJcnKy6ZRNXAgJnVVla+MDhU5PnNh5MKmc1dCjVk= X-Received: by 2002:adf:ce8e:: with SMTP id r14mr11091963wrn.257.1601588800854; Thu, 01 Oct 2020 14:46:40 -0700 (PDT) MIME-Version: 1.0 References: <20201001205819.27879-1-krisman@collabora.com> <20201001205819.27879-5-krisman@collabora.com> In-Reply-To: <20201001205819.27879-5-krisman@collabora.com> From: Andy Lutomirski Date: Thu, 1 Oct 2020 14:46:28 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 4/9] x86: elf: Use e_machine to choose DLINFO in compat To: Gabriel Krisman Bertazi Cc: Andrew Lutomirski , Thomas Gleixner , Christoph Hellwig , "H. Peter Anvin" , Borislav Petkov , Robert Richter , Peter Zijlstra , Ingo Molnar , X86 ML , LKML , Dave Hansen , kernel@collabora.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 1, 2020 at 1:59 PM Gabriel Krisman Bertazi wrote: > > Since TIF_X32 is going away, avoid using it to find the ELF type on > ARCH_DLINFO. > > According to SysV AMD64 ABI Draft, an AMD64 ELF object using ILP32 must > have ELFCLASS32 with (E_MACHINE == EM_X86_64), so use that ELF field to > differentiate a x32 object from a IA32 object when loading ARCH_DLINFO > in compat mode. > Reviewed-by: Andy Lutomirski > Signed-off-by: Gabriel Krisman Bertazi