From patchwork Mon Apr 13 16:21:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 206419 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, 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 38902C352B6 for ; Mon, 13 Apr 2020 16:21:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 18F972072C for ; Mon, 13 Apr 2020 16:21:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586794913; bh=Dha10g8oPUJP+G/98rZMUnPkksDJ6YaGlaXB7AkGC4I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ycAgvUMKbuCo8Pv84Sp9Azx831Ix/hswAdbnbr+FdbKWKktBcU3dyG8LH4FMhLIBX byaDxaQVzt9O++wq3o1D83UDq+74+Gt+oQT4iTuxw81U1EqiGZ+KBDp7es0TDLvpNK pNvkqCK2GlrhTqgOODzVB7ItI4bXFk0/mrsscpDw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731469AbgDMQVw (ORCPT ); Mon, 13 Apr 2020 12:21:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:48876 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731410AbgDMQVw (ORCPT ); Mon, 13 Apr 2020 12:21:52 -0400 Received: from e123331-lin.home (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 823FC2074B; Mon, 13 Apr 2020 16:21:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586794911; bh=Dha10g8oPUJP+G/98rZMUnPkksDJ6YaGlaXB7AkGC4I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iIymU/SNXZ4D5k9/7Z2C98y7snNyAJ98AhVfMu6+lCfLHuKnzm7R34jrUTlNg7Egk ymx7pqhuzGrZzuCzn4ZAeRds3X4zm2KhXDn+PRK5lF0weYWXkhIc3jA5anJAkH9vm/ IEmuDhdWZW0ljWdHucL4HsQ2TyEpVe3KRRFo14OU= 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 Subject: [PATCH v2 3/5] ARM: decompressor: defer loading of the contents of the LC0 structure Date: Mon, 13 Apr 2020 18:21:33 +0200 Message-Id: <20200413162135.14955-4-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200413162135.14955-1-ardb@kernel.org> References: <20200413162135.14955-1-ardb@kernel.org> Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org The remaining contents of LC0 are only used after the point in the decompressor startup code where we enter via 'wont_overwrite'. So move the loading of the LC0 structure after it. This will allow us to jump to wont_overwrite directly from the EFI stub, and execute the decompressor in place at the offset it was loaded by the UEFI firmware. Reviewed-by: Geert Uytterhoeven Signed-off-by: Ard Biesheuvel --- arch/arm/boot/compressed/head.S | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-) diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index 449457d00c4e..9dea394b286b 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -349,10 +349,6 @@ restart: adr r0, LC1 add sp, sp, r0 add r6, r6, r0 - adr r0, LC0 - ldmia r0, {r1, r2, r3, r11, r12} - sub r0, r0, r1 @ calculate the delta offset - get_inflated_image_size r9, r10, lr #ifndef CONFIG_ZBOOT_ROM @@ -370,9 +366,6 @@ restart: adr r0, LC1 mov r5, #0 @ init dtb size to 0 #ifdef CONFIG_ARM_APPENDED_DTB /* - * r0 = delta - * r2 = BSS start - * r3 = BSS end * r4 = final kernel address (possibly with LSB set) * r5 = appended dtb size (still unknown) * r6 = _edata @@ -380,8 +373,6 @@ restart: adr r0, LC1 * r8 = atags/device tree pointer * r9 = size of decompressed image * r10 = end of this image, including bss/stack/malloc space if non XIP - * r11 = GOT start - * r12 = GOT end * sp = stack pointer * * if there are device trees (dtb) appended to zImage, advance r10 so that the @@ -429,7 +420,6 @@ restart: adr r0, LC1 /* temporarily relocate the stack past the DTB work space */ add sp, sp, r5 - stmfd sp!, {r0-r3, ip, lr} mov r0, r8 mov r1, r6 mov r2, r5 @@ -448,7 +438,6 @@ restart: adr r0, LC1 mov r2, r5 bleq atags_to_fdt - ldmfd sp!, {r0-r3, ip, lr} sub sp, sp, r5 #endif @@ -585,6 +574,10 @@ dtb_check_done: mov pc, r0 wont_overwrite: + adr r0, LC0 + ldmia r0, {r1, r2, r3, r11, r12} + sub r0, r0, r1 @ calculate the delta offset + /* * If delta is zero, we are running at the address we were linked at. * r0 = delta