From patchwork Tue May 19 16:26:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 206317 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 0AAC9C433DF for ; Tue, 19 May 2020 16:27:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DF7FD20823 for ; Tue, 19 May 2020 16:27:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589905627; bh=C7HgoJDn2kYqnmr2QmhsUs8JI2aan9kSJKl1W84BSOA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=yVsxir07Zl1L2uDrg9o/iMds2jCKGRl/+UfX8Oe44CIwy29A1/BNEITVFx/+jE09z HcpR1tyCRU4UnfyP+7DICI7HFV03BR9C8hztMWjfPgCz3dkyPAx5GuA9sVd1nNFBMV ecnHKf2PW0lISGgMwSTfmrew6yRryB7uXH07YZso= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728725AbgESQ1H (ORCPT ); Tue, 19 May 2020 12:27:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:41252 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728689AbgESQ1G (ORCPT ); Tue, 19 May 2020 12:27:06 -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 C0249207FB; Tue, 19 May 2020 16:27:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589905626; bh=C7HgoJDn2kYqnmr2QmhsUs8JI2aan9kSJKl1W84BSOA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1oBt2noI2iW40P3wwK0l9PNHZKrkxe+NIZa8eCEdhjgy0nFm8fNmlz3i1YWqaoh3z momG0znFpyDre4CAVNy8I1vwWNBluT/ptuf9gKIaU5KZnmtx1M9muJ1T3wc4bgmdsm oeo3et6vAyCfNgS+qQKm5jyJ1o4t4Cmt8PjWdZ5g= 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 , Heinrich Schuchardt Subject: [PATCH v4 3/5] ARM: decompressor: defer loading of the contents of the LC0 structure Date: Tue, 19 May 2020 18:26:43 +0200 Message-Id: <20200519162645.31065-4-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200519162645.31065-1-ardb@kernel.org> References: <20200519162645.31065-1-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 Reviewed-by: Geert Uytterhoeven Reviewed-by: Nicolas Pitre --- 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 5d712e2c0001..ce442ec5028a 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -299,10 +299,6 @@ 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 @@ -320,9 +316,6 @@ 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 @@ -330,8 +323,6 @@ 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 @@ -379,7 +370,6 @@ 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 @@ -398,7 +388,6 @@ restart: adr r0, LC1 mov r2, r5 bleq atags_to_fdt - ldmfd sp!, {r0-r3, ip, lr} sub sp, sp, r5 #endif @@ -535,6 +524,10 @@ 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