From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Fri, 05 Dec 2014 23:47:23 +0100 (CET) Received: from mail.linuxfoundation.org ([140.211.169.12]:48072 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S27008241AbaLEWqDXmnBY (ORCPT ); Fri, 5 Dec 2014 23:46:03 +0100 Received: from localhost (c-24-22-230-10.hsd1.wa.comcast.net [24.22.230.10]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 00B45A5D; Fri, 5 Dec 2014 22:45:55 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Paul Burton , linux-mips@linux-mips.org, Ralf Baechle Subject: [PATCH 3.17 008/122] MIPS: fix EVA & non-SMP non-FPU FP context signal handling Date: Fri, 5 Dec 2014 14:43:02 -0800 Message-Id: <20141205223306.740952173@linuxfoundation.org> X-Mailer: git-send-email 2.1.3 In-Reply-To: <20141205223305.514276242@linuxfoundation.org> References: <20141205223305.514276242@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: 44598 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 3.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paul Burton commit 14fa12df1d6bc1d3389a0fa842e0ebd8e8a9af26 upstream. The save_fp_context & restore_fp_context pointers were being assigned to the wrong variables if either: - The kernel is configured for UP & runs on a system without an FPU, since b2ead5282885 "MIPS: Move & rename fpu_emulator_{save,restore}_context". - The kernel is configured for EVA, since ca750649e08c "MIPS: kernel: signal: Prevent save/restore FPU context in user memory". This would lead to FP context being clobbered incorrectly when setting up a sigcontext, then the garbage values being saved uselessly when returning from the signal. Fix by swapping the pointer assignments appropriately. Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8230/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman --- arch/mips/kernel/signal.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/mips/kernel/signal.c +++ b/arch/mips/kernel/signal.c @@ -658,13 +658,13 @@ static int signal_setup(void) save_fp_context = _save_fp_context; restore_fp_context = _restore_fp_context; } else { - save_fp_context = copy_fp_from_sigcontext; - restore_fp_context = copy_fp_to_sigcontext; + save_fp_context = copy_fp_to_sigcontext; + restore_fp_context = copy_fp_from_sigcontext; } #endif /* CONFIG_SMP */ #else - save_fp_context = copy_fp_from_sigcontext;; - restore_fp_context = copy_fp_to_sigcontext; + save_fp_context = copy_fp_to_sigcontext; + restore_fp_context = copy_fp_from_sigcontext; #endif return 0;