From patchwork Wed May 6 08:19:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 206357 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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 79276C47258 for ; Wed, 6 May 2020 08:20:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4F4DC20714 for ; Wed, 6 May 2020 08:20:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588753202; bh=s8227r3wr+M1LR2ra2WRSSL45hZ8JOxmjLKJcXVBONI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=z1BnU6mgWdUFfEDDbmDgVeX1yEjv3gn2WYSTzDt2loGFNsfQXawC5rmCXFH7soNuE WrYVw/XP95ue87Rh3gz4pHUq+sZlaYxwK/A0o5R5mog7bH9tcLPBbgJN0K4xkXTUNC Ig9xPgP9/MAvj5OQQBjFhWVtYSE0DICSnW96QEtg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728678AbgEFIUB (ORCPT ); Wed, 6 May 2020 04:20:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:51930 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728398AbgEFIUA (ORCPT ); Wed, 6 May 2020 04:20:00 -0400 Received: from e123331-lin.nice.arm.com (amontpellier-657-1-18-247.w109-210.abo.wanadoo.fr [109.210.65.247]) (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 12A2F207DD; Wed, 6 May 2020 08:19:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588753200; bh=s8227r3wr+M1LR2ra2WRSSL45hZ8JOxmjLKJcXVBONI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h2xi8hwK1/gE7lQNUJRajm7OJOpRAZ4Ex4VugdP6ljnBn3B9u8jnRa9G3ZpSXs6lh FGggTfXmnXdse38q0IPNv3vz584+CRWEHgZxdIuZm694tMcmkxq/cGjWtb1WEQohOM 5QaQ8R5WjE0VYX0/F6ZEWxSTKduJhEPr7ATLw0aE= From: Ard Biesheuvel To: linux-efi@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Ard Biesheuvel , Geert Uytterhoeven , Nicolas Pitre , Linus Walleij , Russell King , Heinrich Schuchardt Subject: [PATCH v3 4/5] ARM: decompressor: move GOT into .data for EFI enabled builds Date: Wed, 6 May 2020 10:19:38 +0200 Message-Id: <20200506081939.8986-5-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200506081939.8986-1-ardb@kernel.org> References: <20200506081939.8986-1-ardb@kernel.org> Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org We will be running the decompressor in place after a future patch, instead of copying it around first. This means we no longer have to disable and re-enable the MMU and caches either. However, this means we will be loaded with the restricted permissions set by the UEFI firmware, which means that we have to move the GOT table into the data section in order for the contents to be writable by the code itself. Signed-off-by: Ard Biesheuvel Reviewed-by: Nicolas Pitre --- arch/arm/boot/compressed/vmlinux.lds.S | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm/boot/compressed/vmlinux.lds.S b/arch/arm/boot/compressed/vmlinux.lds.S index b247f399de71..d0619ec05705 100644 --- a/arch/arm/boot/compressed/vmlinux.lds.S +++ b/arch/arm/boot/compressed/vmlinux.lds.S @@ -63,9 +63,11 @@ SECTIONS _etext = .; .got.plt : { *(.got.plt) } +#ifndef CONFIG_EFI_STUB _got_start = .; .got : { *(.got) } _got_end = .; +#endif /* ensure the zImage file size is always a multiple of 64 bits */ /* (without a dummy byte, ld just ignores the empty section) */ @@ -74,6 +76,9 @@ SECTIONS #ifdef CONFIG_EFI_STUB .data : ALIGN(4096) { __pecoff_data_start = .; + _got_start = .; + *(.got) + _got_end = .; /* * The EFI stub always executes from RAM, and runs strictly before the * decompressor, so we can make an exception for its r/w data, and keep it