From 2e6c7747730296a6d4fd700894286db1132598c4 Mon Sep 17 00:00:00 2001 From: James Hogan Date: Thu, 16 Feb 2017 12:39:01 +0000 Subject: MIPS: Force o32 fp64 support on 32bit MIPS64r6 kernels 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 Cc: # 4.0.x- Patchwork: https://patchwork.linux-mips.org/patch/15310/ Signed-off-by: James Hogan --- arch/mips/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index a008a9f03072..e0bb576410bb 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1531,7 +1531,7 @@ 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 -- cgit v1.2.3