From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755593AbdDJRJJ (ORCPT ); Mon, 10 Apr 2017 13:09:09 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36244 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755509AbdDJQvs (ORCPT ); Mon, 10 Apr 2017 12:51:48 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, James Hogan , Paul Burton , Ralf Baechle , linux-mips@linux-mips.org Subject: [PATCH 4.10 053/110] MIPS: Force o32 fp64 support on 32bit MIPS64r6 kernels Date: Mon, 10 Apr 2017 18:42:44 +0200 Message-Id: <20170410164204.199974825@linuxfoundation.org> X-Mailer: git-send-email 2.12.2 In-Reply-To: <20170410164201.247583164@linuxfoundation.org> References: <20170410164201.247583164@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 4.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: James Hogan commit 2e6c7747730296a6d4fd700894286db1132598c4 upstream. When a 32-bit kernel is configured to support MIPS64r6 (CPU_MIPS64_R6), MIPS_O32_FP64_SUPPORT won't be selected as it should be because MIPS32_O32 is disabled (o32 is already the default ABI available on 32-bit kernels). This results in userland FP breakage as CP0_Status.FR is read-only 1 since r6 (when an FPU is present) so __enable_fpu() will fail to clear FR. This causes the FPU emulator to get used which will incorrectly emulate 32-bit FPU registers. Force o32 fp64 support in this case by also selecting MIPS_O32_FP64_SUPPORT from CPU_MIPS64_R6 if 32BIT. Fixes: 4e9d324d4288 ("MIPS: Require O32 FP64 support for MIPS64 with O32 compat") Signed-off-by: James Hogan Reviewed-by: Paul Burton Cc: Ralf Baechle Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/15310/ Signed-off-by: James Hogan Signed-off-by: Greg Kroah-Hartman --- arch/mips/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1526,7 +1526,7 @@ config CPU_MIPS64_R6 select CPU_SUPPORTS_HIGHMEM select CPU_SUPPORTS_MSA select GENERIC_CSUM - select MIPS_O32_FP64_SUPPORT if MIPS32_O32 + select MIPS_O32_FP64_SUPPORT if 32BIT || MIPS32_O32 select HAVE_KVM help Choose this option to build a kernel for release 6 or later of the