| From 8b3b005d675726e38bc504d2e35a991e55819155 Mon Sep 17 00:00:00 2001 |
| From: "H. Peter Anvin" <hpa@linux.intel.com> |
| Date: Mon, 9 Dec 2013 15:43:38 -0800 |
| Subject: x86, build: Pass in additional -mno-mmx, -mno-sse options |
| |
| From: "H. Peter Anvin" <hpa@linux.intel.com> |
| |
| commit 8b3b005d675726e38bc504d2e35a991e55819155 upstream. |
| |
| In checkin |
| |
| 5551a34e5aea x86-64, build: Always pass in -mno-sse |
| |
| we unconditionally added -mno-sse to the main build, to keep newer |
| compilers from generating SSE instructions from autovectorization. |
| However, this did not extend to the special environments |
| (arch/x86/boot, arch/x86/boot/compressed, and arch/x86/realmode/rm). |
| Add -mno-sse to the compiler command line for these environments, and |
| add -mno-mmx to all the environments as well, as we don't want a |
| compiler to generate MMX code either. |
| |
| This patch also removes a $(cc-option) call for -m32, since we have |
| long since stopped supporting compilers too old for the -m32 option, |
| and in fact hardcode it in other places in the Makefiles. |
| |
| Reported-by: Kevin B. Smith <kevin.b.smith@intel.com> |
| Cc: Sunil K. Pandey <sunil.k.pandey@intel.com> |
| Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> |
| Cc: H. J. Lu <hjl.tools@gmail.com> |
| Link: http://lkml.kernel.org/n/tip-j21wzqv790q834n7yc6g80j1@git.kernel.org |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| arch/x86/Makefile | 8 ++++---- |
| arch/x86/boot/Makefile | 6 +++--- |
| arch/x86/boot/compressed/Makefile | 1 + |
| arch/x86/realmode/rm/Makefile | 3 ++- |
| 4 files changed, 10 insertions(+), 8 deletions(-) |
| |
| --- a/arch/x86/Makefile |
| +++ b/arch/x86/Makefile |
| @@ -31,8 +31,8 @@ ifeq ($(CONFIG_X86_32),y) |
| |
| KBUILD_CFLAGS += -msoft-float -mregparm=3 -freg-struct-return |
| |
| - # Don't autogenerate SSE instructions |
| - KBUILD_CFLAGS += -mno-sse |
| + # Don't autogenerate MMX or SSE instructions |
| + KBUILD_CFLAGS += -mno-mmx -mno-sse |
| |
| # Never want PIC in a 32-bit kernel, prevent breakage with GCC built |
| # with nonstandard options |
| @@ -60,8 +60,8 @@ else |
| KBUILD_AFLAGS += -m64 |
| KBUILD_CFLAGS += -m64 |
| |
| - # Don't autogenerate SSE instructions |
| - KBUILD_CFLAGS += -mno-sse |
| + # Don't autogenerate MMX or SSE instructions |
| + KBUILD_CFLAGS += -mno-mmx -mno-sse |
| |
| # Use -mpreferred-stack-boundary=3 if supported. |
| KBUILD_CFLAGS += $(call cc-option,-mpreferred-stack-boundary=3) |
| --- a/arch/x86/boot/Makefile |
| +++ b/arch/x86/boot/Makefile |
| @@ -53,18 +53,18 @@ $(obj)/cpustr.h: $(obj)/mkcpustr FORCE |
| |
| # How to compile the 16-bit code. Note we always compile for -march=i386, |
| # that way we can complain to the user if the CPU is insufficient. |
| -KBUILD_CFLAGS := $(USERINCLUDE) -g -Os -D_SETUP -D__KERNEL__ \ |
| +KBUILD_CFLAGS := $(USERINCLUDE) -m32 -g -Os -D_SETUP -D__KERNEL__ \ |
| -DDISABLE_BRANCH_PROFILING \ |
| -Wall -Wstrict-prototypes \ |
| -march=i386 -mregparm=3 \ |
| -include $(srctree)/$(src)/code16gcc.h \ |
| -fno-strict-aliasing -fomit-frame-pointer -fno-pic \ |
| + -mno-mmx -mno-sse \ |
| $(call cc-option, -ffreestanding) \ |
| $(call cc-option, -fno-toplevel-reorder,\ |
| - $(call cc-option, -fno-unit-at-a-time)) \ |
| + $(call cc-option, -fno-unit-at-a-time)) \ |
| $(call cc-option, -fno-stack-protector) \ |
| $(call cc-option, -mpreferred-stack-boundary=2) |
| -KBUILD_CFLAGS += $(call cc-option, -m32) |
| KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__ |
| GCOV_PROFILE := n |
| |
| --- a/arch/x86/boot/compressed/Makefile |
| +++ b/arch/x86/boot/compressed/Makefile |
| @@ -12,6 +12,7 @@ KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFIL |
| cflags-$(CONFIG_X86_32) := -march=i386 |
| cflags-$(CONFIG_X86_64) := -mcmodel=small |
| KBUILD_CFLAGS += $(cflags-y) |
| +KBUILD_CFLAGS += -mno-mmx -mno-sse |
| KBUILD_CFLAGS += $(call cc-option,-ffreestanding) |
| KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector) |
| |
| --- a/arch/x86/realmode/rm/Makefile |
| +++ b/arch/x86/realmode/rm/Makefile |
| @@ -73,9 +73,10 @@ KBUILD_CFLAGS := $(LINUXINCLUDE) -m32 -g |
| -march=i386 -mregparm=3 \ |
| -include $(srctree)/$(src)/../../boot/code16gcc.h \ |
| -fno-strict-aliasing -fomit-frame-pointer -fno-pic \ |
| + -mno-mmx -mno-sse \ |
| $(call cc-option, -ffreestanding) \ |
| $(call cc-option, -fno-toplevel-reorder,\ |
| - $(call cc-option, -fno-unit-at-a-time)) \ |
| + $(call cc-option, -fno-unit-at-a-time)) \ |
| $(call cc-option, -fno-stack-protector) \ |
| $(call cc-option, -mpreferred-stack-boundary=2) |
| KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__ |
