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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 7DE26C282DA for ; Sun, 3 Feb 2019 14:30:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 492182073D for ; Sun, 3 Feb 2019 14:30:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731066AbfBCOae (ORCPT ); Sun, 3 Feb 2019 09:30:34 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:55326 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729708AbfBCOUO (ORCPT ); Sun, 3 Feb 2019 09:20:14 -0500 Received: from cable-78.29.236.164.coditel.net ([78.29.236.164] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gqId1-0006EN-23; Sun, 03 Feb 2019 14:20:11 +0000 Received: from ben by deadeye with local (Exim 4.92-RC4) (envelope-from ) id 1gqI9m-0007J0-Iw; Sun, 03 Feb 2019 14:49:58 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Paul Mackerras" , "Michael Ellerman" Date: Sun, 03 Feb 2019 14:45:08 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 236/305] powerpc: Fix COFF zImage booting on old powermacs In-Reply-To: X-SA-Exim-Connect-IP: 78.29.236.164 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.63-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Paul Mackerras commit 5564597d51c8ff5b88d95c76255e18b13b760879 upstream. Commit 6975a783d7b4 ("powerpc/boot: Allow building the zImage wrapper as a relocatable ET_DYN", 2011-04-12) changed the procedure descriptor at the start of crt0.S to have a hard-coded start address of 0x500000 rather than a reference to _zimage_start, presumably because having a reference to a symbol introduced a relocation which is awkward to handle in a position-independent executable. Unfortunately, what is at 0x500000 in the COFF image is not the first instruction, but the procedure descriptor itself, that is, a word containing 0x500000, which is not a valid instruction. Hence, booting a COFF zImage results in a "DEFAULT CATCH!, code=FFF00700" message from Open Firmware. This fixes the problem by (a) putting the procedure descriptor in the data section and (b) adding a branch to _zimage_start as the first instruction in the program. Fixes: 6975a783d7b4 ("powerpc/boot: Allow building the zImage wrapper as a relocatable ET_DYN") Signed-off-by: Paul Mackerras Signed-off-by: Michael Ellerman Signed-off-by: Ben Hutchings --- arch/powerpc/boot/crt0.S | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/arch/powerpc/boot/crt0.S +++ b/arch/powerpc/boot/crt0.S @@ -15,7 +15,7 @@ RELA = 7 RELACOUNT = 0x6ffffff9 - .text + .data /* A procedure descriptor used when booting this as a COFF file. * When making COFF, this comes first in the link and we're * linked at 0x500000. @@ -23,6 +23,8 @@ RELACOUNT = 0x6ffffff9 .globl _zimage_start_opd _zimage_start_opd: .long 0x500000, 0, 0, 0 + .text + b _zimage_start #ifdef __powerpc64__ .balign 8