diff options
| author | Paul Burton <paul.burton@mips.com> | 2019-10-10 18:54:03 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-10-17 13:42:45 -0700 |
| commit | 83c3684d71eba85d8020e345e08d9b1ba2d3a922 (patch) | |
| tree | 72f9b7c10402e5d279a7ff18cb8ff86787e13a08 | |
| parent | 82143aa25f4e5f193401024c3b25fbc70d992525 (diff) | |
MIPS: Disable Loongson MMI instructions for kernel build
commit 2f2b4fd674cadd8c6b40eb629e140a14db4068fd upstream.
GCC 9.x automatically enables support for Loongson MMI instructions when
using some -march= flags, and then errors out when -msoft-float is
specified with:
cc1: error: ‘-mloongson-mmi’ must be used with ‘-mhard-float’
The kernel shouldn't be using these MMI instructions anyway, just as it
doesn't use floating point instructions. Explicitly disable them in
order to fix the build with GCC 9.x.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 3702bba5eb4f ("MIPS: Loongson: Add GCC 4.4 support for Loongson2E")
Fixes: 6f7a251a259e ("MIPS: Loongson: Add basic Loongson 2F support")
Fixes: 5188129b8c9f ("MIPS: Loongson-3: Improve -march option and move it to Platform")
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: stable@vger.kernel.org # v2.6.32+
Cc: linux-mips@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/mips/loongson64/Platform | 4 | ||||
| -rw-r--r-- | arch/mips/vdso/Makefile | 1 |
2 files changed, 5 insertions, 0 deletions
diff --git a/arch/mips/loongson64/Platform b/arch/mips/loongson64/Platform index 0fce4608aa88..12abf14aed4a 100644 --- a/arch/mips/loongson64/Platform +++ b/arch/mips/loongson64/Platform @@ -43,6 +43,10 @@ else $(call cc-option,-march=mips64r2,-mips64r2 -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS64) endif +# Some -march= flags enable MMI instructions, and GCC complains about that +# support being enabled alongside -msoft-float. Thus explicitly disable MMI. +cflags-y += $(call cc-option,-mno-loongson-mmi) + # # Loongson Machines' Support # diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile index 247ca2e9add9..adfaee2dce34 100644 --- a/arch/mips/vdso/Makefile +++ b/arch/mips/vdso/Makefile @@ -8,6 +8,7 @@ ccflags-vdso := \ $(filter -mmicromips,$(KBUILD_CFLAGS)) \ $(filter -march=%,$(KBUILD_CFLAGS)) \ $(filter -m%-float,$(KBUILD_CFLAGS)) \ + $(filter -mno-loongson-%,$(KBUILD_CFLAGS)) \ -D__VDSO__ cflags-vdso := $(ccflags-vdso) \ $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \ |