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=-8.5 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT 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 693F0C433F4 for ; Mon, 24 Sep 2018 20:15:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0BE262145D for ; Mon, 24 Sep 2018 20:15:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0BE262145D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727347AbeIYCT0 (ORCPT ); Mon, 24 Sep 2018 22:19:26 -0400 Received: from mga01.intel.com ([192.55.52.88]:26545 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727281AbeIYCT0 (ORCPT ); Mon, 24 Sep 2018 22:19:26 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 24 Sep 2018 13:15:31 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,299,1534834800"; d="scan'208";a="265335190" Received: from gnu-4.sc.intel.com ([172.25.70.231]) by fmsmga005.fm.intel.com with ESMTP; 24 Sep 2018 13:14:59 -0700 From: "H.J. Lu" To: linux-kernel@vger.kernel.org Cc: Yu-cheng Yu Subject: [PATCH] x86: Discard .note.gnu.property sections Date: Mon, 24 Sep 2018 13:14:59 -0700 Message-Id: <20180924201459.35923-1-hjl.tools@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org With the command-line option, -mx86-used-note=yes, the x86 assembler in binutils 2.32 and above generates a program property note in a note section, .note.gnu.property, to encode used x86 ISAs and features. To exclude .note.gnu.property sections from NOTE segment in x86 kernel linker script: PHDRS { text PT_LOAD FLAGS(5); data PT_LOAD FLAGS(6); percpu PT_LOAD FLAGS(6); init PT_LOAD FLAGS(7); note PT_NOTE FLAGS(0); } SECTIONS { ... .notes : AT(ADDR(.notes) - 0xffffffff80000000) { __start_notes = .; KEEP(*(.not e.*)) __stop_notes = .; } :text :note ... } this patch discards .note.gnu.property sections in kernel linker script by adding /DISCARD/ : { *(.note.gnu.property) } before .notes sections. Since .exit.text and .exit.data sections are discarded at runtime, it undefines EXIT_TEXT and EXIT_DATA to exclude .exit.text and .exit.data sections from default discarded sections. Signed-off-by: H.J. Lu --- arch/x86/kernel/vmlinux.lds.S | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 8bde0a419f86..7e1e0ef1578a 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -138,6 +138,10 @@ SECTIONS _etext = .; } :text = 0x9090 + /* .note.gnu.property sections should be discarded */ + /DISCARD/ : { + *(.note.gnu.property) + } NOTES :text :note EXCEPTION_TABLE(16) :text = 0x9090 @@ -373,7 +377,12 @@ SECTIONS STABS_DEBUG DWARF_DEBUG - /* Sections to be discarded */ + /* Sections to be discarded. EXIT_TEXT and EXIT_DATA discard at runtime. + * not link time. */ +#undef EXIT_TEXT +#define EXIT_TEXT +#undef EXIT_DATA +#define EXIT_DATA DISCARDS /DISCARD/ : { *(.eh_frame) -- 2.17.1