From patchwork Fri Mar 27 10:59:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 206439 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 08958C2D0E8 for ; Fri, 27 Mar 2020 10:59:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D29EA20705 for ; Fri, 27 Mar 2020 10:59:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585306769; bh=JkfI/Yz/aTq4fkf6UNHJYhxxoI5M+vw7HbOburdO3DU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=fe9Daad3rbH8fgFvaNRdzDYur47+Ltn8sQuvDLjF3cUIPOvrjawPvV3lUHVBF72jO zl/7h830Ypa9fLQskm/unnza3S0xi/4gthWlQGtUiqb3CMA9Vd9eLoMRLaObhQ3RyU m33SSULMKtqeaKIaInFjlPhWcb1+q7t3T75O9elk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726515AbgC0K73 (ORCPT ); Fri, 27 Mar 2020 06:59:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:59208 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726165AbgC0K73 (ORCPT ); Fri, 27 Mar 2020 06:59:29 -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 0F08C2074F; Fri, 27 Mar 2020 10:59:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585306768; bh=JkfI/Yz/aTq4fkf6UNHJYhxxoI5M+vw7HbOburdO3DU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uVwIzVcxUN5ZA7n5X82mv+eWvPfx4GjnutX1aaKybnhCdtWVj7bfq7Ep1NxwVOeKg c00FK1h+ESwMH/b343vJxcQ9/pOVV7wazOuwRhU83Zw6NA9wBl2O3os8CgDpFpTdsw zgsXtwxoGxHLjAeoejKntj050uuxisxIKgP+egeE= From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Cc: linux-efi@vger.kernel.org, Ard Biesheuvel , Geert Uytterhoeven , Nicolas Pitre , Linus Walleij , Russell King Subject: [PATCH 3/5] ARM: decompressor: defer loading of the contents of the LC0 structure Date: Fri, 27 Mar 2020 11:59:04 +0100 Message-Id: <20200327105906.2665-4-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200327105906.2665-1-ardb@kernel.org> References: <20200327105906.2665-1-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. 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 a6cf2f8115e5..35d4db00eaf9 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -347,10 +347,6 @@ restart: adr r0, LC1 add sp, r1, 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 @@ -368,9 +364,6 @@ 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 @@ -378,8 +371,6 @@ 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 @@ -427,7 +418,6 @@ 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 @@ -446,7 +436,6 @@ restart: adr r0, LC1 mov r2, r5 bleq atags_to_fdt - ldmfd sp!, {r0-r3, ip, lr} sub sp, sp, r5 #endif @@ -583,6 +572,10 @@ 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