From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759916Ab3LBVY5 (ORCPT ); Mon, 2 Dec 2013 16:24:57 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:38328 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753413Ab3LBTHV (ORCPT ); Mon, 2 Dec 2013 14:07:21 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Andreas=20Bie=C3=9Fmann?= , Hans-Christian Egtvedt , Haavard Skinnemoen Subject: [PATCH 3.4 42/60] avr32: fix out-of-range jump in large kernels Date: Mon, 2 Dec 2013 11:06:23 -0800 Message-Id: <20131202190339.404868867@linuxfoundation.org> X-Mailer: git-send-email 1.8.4.3.gca3854a In-Reply-To: <20131202190330.152596462@linuxfoundation.org> References: <20131202190330.152596462@linuxfoundation.org> User-Agent: quilt/0.60-8.1.3 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andreas Bießmann commit d617b338bbfdd77e9cbd8e7dc949cee3dd73d575 upstream. This patch fixes following error (for big kernels): ---8<--- arch/avr32/boot/u-boot/head.o: In function `no_tag_table': (.init.text+0x44): relocation truncated to fit: R_AVR32_22H_PCREL against symbol `panic' defined in .text.unlikely section in kernel/built-in.o arch/avr32/kernel/built-in.o: In function `bad_return': (.ex.text+0x236): relocation truncated to fit: R_AVR32_22H_PCREL against symbol `panic' defined in .text.unlikely section in kernel/built-in.o --->8--- It comes up when the kernel increases and 'panic()' is too far away to fit in the +/- 2MiB range. Which in turn issues from the 21-bit displacement in 'br{cond4}' mnemonic which is one of the two ways to do jumps (rjmp has just 10-bit displacement and therefore a way smaller range). This fact was stated before in 8d29b7b9f81d6b83d869ff054e6c189d6da73f1f. One solution to solve this is to add a local storage for the symbol address and just load the $pc with that value. Signed-off-by: Andreas Bießmann Acked-by: Hans-Christian Egtvedt Cc: Haavard Skinnemoen Signed-off-by: Greg Kroah-Hartman --- arch/avr32/boot/u-boot/head.S | 5 ++++- arch/avr32/kernel/entry-avr32b.S | 3 ++- 2 files changed, 6 insertions(+), 2 deletions(-) --- a/arch/avr32/boot/u-boot/head.S +++ b/arch/avr32/boot/u-boot/head.S @@ -73,8 +73,11 @@ init_sr: .long 0x007f0000 /* Supervisor mode, everything masked */ stack_addr: .long init_thread_union +panic_addr: + .long panic no_tag_table: sub r12, pc, (. - 2f) - bral panic + /* branch to panic() which can be far away with that construct */ + lddpc pc, panic_addr 2: .asciz "Boot loader didn't provide correct magic number\n" --- a/arch/avr32/kernel/entry-avr32b.S +++ b/arch/avr32/kernel/entry-avr32b.S @@ -399,9 +399,10 @@ handle_critical: /* We should never get here... */ bad_return: sub r12, pc, (. - 1f) - bral panic + lddpc pc, 2f .align 2 1: .asciz "Return from critical exception!" +2: .long panic .align 1 do_bus_error_write: