From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Fri, 03 Oct 2014 23:43:27 +0200 (CEST) Received: from mail.linuxfoundation.org ([140.211.169.12]:56427 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S27010511AbaJCVnHZa06u (ORCPT ); Fri, 3 Oct 2014 23:43:07 +0200 Received: from localhost (c-24-22-230-10.hsd1.wa.comcast.net [24.22.230.10]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 17FE8B31; Fri, 3 Oct 2014 21:43:00 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Markos Chandras , linux-mips@linux-mips.org, Ralf Baechle Subject: [PATCH 3.16 194/357] MIPS: mcount: Adjust stack pointer for static trace in MIPS32 Date: Fri, 3 Oct 2014 14:29:40 -0700 Message-Id: <20141003212939.303109449@linuxfoundation.org> X-Mailer: git-send-email 2.1.2 In-Reply-To: <20141003212933.458851516@linuxfoundation.org> References: <20141003212933.458851516@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 42942 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: gregkh@linuxfoundation.org Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips 3.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Markos Chandras commit 8a574cfa2652545eb95595d38ac2a0bb501af0ae upstream. Every mcount() call in the MIPS 32-bit kernel is done as follows: [...] move at, ra jal _mcount addiu sp, sp, -8 [...] but upon returning from the mcount() function, the stack pointer is not adjusted properly. This is explained in details in 58b69401c797 (MIPS: Function tracer: Fix broken function tracing). Commit ad8c396936e3 ("MIPS: Unbreak function tracer for 64-bit kernel.) fixed the stack manipulation for 64-bit but it didn't fix it completely for MIPS32. Signed-off-by: Markos Chandras Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7792/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman --- arch/mips/kernel/mcount.S | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/arch/mips/kernel/mcount.S +++ b/arch/mips/kernel/mcount.S @@ -123,7 +123,11 @@ NESTED(_mcount, PT_SIZE, ra) nop #endif b ftrace_stub +#ifdef CONFIG_32BIT + addiu sp, sp, 8 +#else nop +#endif static_trace: MCOUNT_SAVE_REGS @@ -133,6 +137,9 @@ static_trace: move a1, AT /* arg2: parent's return address */ MCOUNT_RESTORE_REGS +#ifdef CONFIG_32BIT + addiu sp, sp, 8 +#endif .globl ftrace_stub ftrace_stub: RETURN_BACK @@ -177,6 +184,11 @@ NESTED(ftrace_graph_caller, PT_SIZE, ra) jal prepare_ftrace_return nop MCOUNT_RESTORE_REGS +#ifndef CONFIG_DYNAMIC_FTRACE +#ifdef CONFIG_32BIT + addiu sp, sp, 8 +#endif +#endif RETURN_BACK END(ftrace_graph_caller)