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=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 9DDB7C38BE2 for ; Mon, 24 Feb 2020 20:49:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 71900218AC for ; Mon, 24 Feb 2020 20:49:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="OczUm8C+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727500AbgBXUtR (ORCPT ); Mon, 24 Feb 2020 15:49:17 -0500 Received: from mail-pf1-f193.google.com ([209.85.210.193]:34021 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727249AbgBXUtQ (ORCPT ); Mon, 24 Feb 2020 15:49:16 -0500 Received: by mail-pf1-f193.google.com with SMTP id i6so5967285pfc.1 for ; Mon, 24 Feb 2020 12:49:15 -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=Knih+VN2aCDc/a1HoFO7myAtDlhjV/MlW8P0R3Lsz6k=; b=OczUm8C+dyhkoniILj5vfVY4thaCbz21wL2o4W1iPYLN9C4renHakPjsF0wN0R7/PK ROPGME4HFALbizqzw1uzuow6v90oO21JNpQ0Hr7lrx+A0wR64NqvDttBrP4paCpdWnJb lOLBYJKGbEys0X6LmeU5FRf/32pR3JtoRkOVvDP57MCLKY9KimfY+2nzfYJEmKoNRBYJ /h6lqh0bL7uHCyZcI/GWe7et69cavIHc2Z8/zf1f2QCxsl5E4QCUwqtxu2quIDIDBgfQ nUtI6hXUyfh3TWoZCpwPyFAfAnEo+DBDvtiD0vepaVwWYKW+1vr6W6KOI+b1XU/sur8P TwmQ== 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=Knih+VN2aCDc/a1HoFO7myAtDlhjV/MlW8P0R3Lsz6k=; b=tYi6YsJjZ+BNp/+ZggdaGIl2MobmtOZvXlVNyMUnLKLKqexp3gAusyt8H8UaQj/0o9 ZmJuaWhp84m+N+Qm9ZZVqY2RKz8/2bk1ufdI52ffNNIbDs0yACrmI/AAez1pvp6vL1H0 iKN1qw8+Z6bP18q1teg4C0+Yu2wX693U6rEOYae7wiiWrexavZICIBpwGRxTV3ETv++k NPgDcrWnSoHmceqiHAReoeKZN4I7C1mduCPHw6fmTyDLHRCYF0Vjxcfg7IW7tgunE6E8 MklDeiND7CMcVV9eHnHiDTB/rDbNOayVHO3KdAs3ehz4lHvD4hQoO8ZGQ7GtawbjfPRK kRBw== X-Gm-Message-State: APjAAAWV7RqmbuHvKZHhqHnxyqLt5WgOGslsQQfl/eYFEOyPaJwshMQI BKhUdyumAKHQOhapcPqn4el9T4MTUzCYDZnuRii5bg== X-Google-Smtp-Source: APXvYqw/5xtBB4M8e/Uzl06X/DNHHJ4sVpSAPy5BInZBQUvOdUmCLpLw5WP2Xnfzc1QQidBPvN+2ZD6FIeRUpJsUdTc= X-Received: by 2002:a63:4453:: with SMTP id t19mr17312657pgk.381.1582577354652; Mon, 24 Feb 2020 12:49:14 -0800 (PST) MIME-Version: 1.0 References: <20200222235709.GA3786197@rani.riverdale.lan> <20200223193715.83729-1-nivedita@alum.mit.edu> In-Reply-To: <20200223193715.83729-1-nivedita@alum.mit.edu> From: Nick Desaulniers Date: Mon, 24 Feb 2020 12:49:03 -0800 Message-ID: Subject: Re: [PATCH 0/2] Stop generating .eh_frame sections To: Arvind Sankar Cc: Borislav Petkov , Nathan Chancellor , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , LKML , clang-built-linux , Michael Matz , Fangrui Song , Kees Cook 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 Sun, Feb 23, 2020 at 11:37 AM Arvind Sankar wrote: > > In three places in the x86 kernel we are currently generating .eh_frame > sections only to discard them later via linker script. This is in the > boot code (setup.elf), the realmode trampoline (realmode.elf) and the > compressed kernel. > > Implement Fangrui and Nick's suggestion [1] to fix KBUILD_CFLAGS by > adding -fno-asynchronous-unwind-tables to avoid generating .eh_frame > sections in the first place, rather than discarding it in the linker > script. > > Arvind Sankar (2): > arch/x86: Use -fno-asynchronous-unwind-tables to suppress .eh_frame sections > arch/x86: Drop unneeded linker script discard of .eh_frame Thanks for the series! I've left some feedback for a v2. Would you mind please including a revert of ("x86/boot/compressed: Remove unnecessary sections from bzImage") in a v2 series? Our CI being red through the weekend is no bueno. > > arch/x86/boot/Makefile | 1 + > arch/x86/boot/compressed/Makefile | 1 + > arch/x86/boot/setup.ld | 1 - > arch/x86/kernel/vmlinux.lds.S | 3 --- > arch/x86/realmode/rm/Makefile | 1 + > arch/x86/realmode/rm/realmode.lds.S | 1 - > drivers/firmware/efi/libstub/Makefile | 3 ++- > 7 files changed, 5 insertions(+), 6 deletions(-) > > -- > 2.24.1 > -- Thanks, ~Nick Desaulniers