From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935426AbdEKOYc (ORCPT ); Thu, 11 May 2017 10:24:32 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:47476 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935385AbdEKOY1 (ORCPT ); Thu, 11 May 2017 10:24:27 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Leonid Yegoshin , Nikola.Veljkovic@imgtec.com, paul.burton@imgtec.com, yamada.masahiro@socionext.com, akpm@linux-foundation.org, andrea.gelmini@gelma.net, macro@imgtec.com, linux-mips@linux-mips.org, Ralf Baechle Subject: [PATCH 4.9 075/103] MIPS: R2-on-R6 MULTU/MADDU/MSUBU emulation bugfix Date: Thu, 11 May 2017 16:12:44 +0200 Message-Id: <20170511141216.553421448@linuxfoundation.org> X-Mailer: git-send-email 2.12.2 In-Reply-To: <20170511141210.778405364@linuxfoundation.org> References: <20170511141210.778405364@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Leonid Yegoshin commit d65e5677ad5b3a49c43f60ec07644dc1f87bbd2e upstream. MIPS instructions MULTU, MADDU and MSUBU emulation requires registers HI/LO to be converted to signed 32bits before 64bit sign extension on MIPS64. Bug was found on running MIPS32 R2 test application on MIPS64 R6 kernel. Fixes: b0a668fb2038 ("MIPS: kernel: mips-r2-to-r6-emul: Add R2 emulator for MIPS R6") Signed-off-by: Leonid Yegoshin Reported-by: Nikola.Veljkovic@imgtec.com Cc: paul.burton@imgtec.com Cc: yamada.masahiro@socionext.com Cc: akpm@linux-foundation.org Cc: andrea.gelmini@gelma.net Cc: macro@imgtec.com Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14043/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman --- arch/mips/kernel/mips-r2-to-r6-emul.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/arch/mips/kernel/mips-r2-to-r6-emul.c +++ b/arch/mips/kernel/mips-r2-to-r6-emul.c @@ -433,8 +433,8 @@ static int multu_func(struct pt_regs *re rs = regs->regs[MIPSInst_RS(ir)]; res = (u64)rt * (u64)rs; rt = res; - regs->lo = (s64)rt; - regs->hi = (s64)(res >> 32); + regs->lo = (s64)(s32)rt; + regs->hi = (s64)(s32)(res >> 32); MIPS_R2_STATS(muls); @@ -670,9 +670,9 @@ static int maddu_func(struct pt_regs *re res += ((((s64)rt) << 32) | (u32)rs); rt = res; - regs->lo = (s64)rt; + regs->lo = (s64)(s32)rt; rs = res >> 32; - regs->hi = (s64)rs; + regs->hi = (s64)(s32)rs; MIPS_R2_STATS(dsps); @@ -728,9 +728,9 @@ static int msubu_func(struct pt_regs *re res = ((((s64)rt) << 32) | (u32)rs) - res; rt = res; - regs->lo = (s64)rt; + regs->lo = (s64)(s32)rt; rs = res >> 32; - regs->hi = (s64)rs; + regs->hi = (s64)(s32)rs; MIPS_R2_STATS(dsps);