From patchwork Wed Sep 2 06:23:29 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Robert Jarzmik X-Patchwork-Id: 7108641 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id E9EB69F1D5 for ; Wed, 2 Sep 2015 06:30:46 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1299B2053C for ; Wed, 2 Sep 2015 06:30:46 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 37E622052C for ; Wed, 2 Sep 2015 06:30:45 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZX1XA-00029t-BK; Wed, 02 Sep 2015 06:28:36 +0000 Received: from smtp04.smtpout.orange.fr ([80.12.242.126] helo=smtp.smtpout.orange.fr) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZX1X8-0001tq-4O for linux-arm-kernel@lists.infradead.org; Wed, 02 Sep 2015 06:28:35 +0000 Received: from belgarion.home ([109.222.247.56]) by mwinf5d39 with ME id C6U91r00T1DkrDp036U9CW; Wed, 02 Sep 2015 08:28:10 +0200 X-ME-Helo: belgarion.home X-ME-Date: Wed, 02 Sep 2015 08:28:10 +0200 X-ME-IP: 109.222.247.56 From: Robert Jarzmik To: Russell King - ARM Linux Subject: [PATCH] ARM: fix alignement of __bug_table section entries Date: Wed, 2 Sep 2015 08:23:29 +0200 Message-Id: <1441175009-26730-1-git-send-email-robert.jarzmik@free.fr> X-Mailer: git-send-email 2.1.4 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150901_232834_512394_B9AD8596 X-CRM114-Status: GOOD ( 15.19 ) X-Spam-Score: -1.9 (-) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Robert Jarzmik , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00,FREEMAIL_FROM, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On old ARM chips, unaligned accesses to memory are not trapped and fixed. On module load, symbols are relocated, and the relocation of __bug_table symbols is done on a u32 basis. Yet the section is not aligned to a multiple of 4 address, but to a multiple of 2. This triggers an Oops on pxa architecture, where address 0xbf0021ea is the first relocation in the __bug_table section : apply_relocate(): pxa3xx_nand: section 13 reloc 0 sym '' Unable to handle kernel paging request at virtual address bf0021ea pgd = e1cd0000 [bf0021ea] *pgd=c1cce851, *pte=c1cde04f, *ppte=c1cde01f Internal error: Oops: 23 [#1] ARM Modules linked in: CPU: 0 PID: 606 Comm: insmod Not tainted 4.2.0-rc8-next-20150828-cm-x300+ #887 Hardware name: CM-X300 module task: e1c68700 ti: e1c3e000 task.ti: e1c3e000 PC is at apply_relocate+0x2f4/0x3d4 LR is at 0xbf0021ea pc : [] lr : [] psr: 80000013 sp : e1c3fe30 ip : 60000013 fp : e49e8c60 r10: e49e8fa8 r9 : 00000000 r8 : e49e7c58 r7 : e49e8c38 r6 : e49e8a58 r5 : e49e8920 r4 : e49e8918 r3 : bf0021ea r2 : bf007034 r1 : 00000000 r0 : bf000000 Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 0000397f Table: c1cd0018 DAC: 00000051 Process insmod (pid: 606, stack limit = 0xe1c3e198) [] (apply_relocate) from [] (load_module+0x1248/0x1f5c) [] (load_module) from [] (SyS_init_module+0xe4/0x170) [] (SyS_init_module) from [] (ret_fast_syscall+0x0/0x38) Fix this by ensuring entries in __bug_table are all aligned to at least of multiple of 4. This transforms a module section __bug_table as : - [12] __bug_table PROGBITS 00000000 002232 000018 00 A 0 0 1 + [12] __bug_table PROGBITS 00000000 002232 000018 00 A 0 0 4 Signed-off-by: Robert Jarzmik Reviewed-by: Dave Martin --- arch/arm/include/asm/bug.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm/include/asm/bug.h b/arch/arm/include/asm/bug.h index b274bde24905..e7335a92144e 100644 --- a/arch/arm/include/asm/bug.h +++ b/arch/arm/include/asm/bug.h @@ -40,6 +40,7 @@ do { \ "2:\t.asciz " #__file "\n" \ ".popsection\n" \ ".pushsection __bug_table,\"a\"\n" \ + ".align 2\n" \ "3:\t.word 1b, 2b\n" \ "\t.hword " #__line ", 0\n" \ ".popsection"); \