diff options
| author | H. Peter Anvin <hpa@zytor.com> | 2009-12-25 18:40:38 -0500 |
|---|---|---|
| committer | H. Peter Anvin <hpa@zytor.com> | 2009-12-25 18:40:38 -0500 |
| commit | 17a2a9b57a9a7d2fd8f97df951b5e63e0bd56ef5 (patch) | |
| tree | 4835ed4adac9ab7a4ee6e550557f71fd823dc70c /arch/x86/boot | |
| parent | 8bee738bb1979c8bf7b42716b772522ab7d26b0c (diff) | |
x86, compress: Force i386 instructions for the decompressor
Recently, some distros have started shipping versions of gcc which
default to -march=i686. This breaks building kernels for pre-i686
machines, even if they have been selected in Kconfig, due to the
generation of CMOV instructions.
There isn't enough benefit to try to preserve the generation of these
instructions even when selected, so simply force -march=i386 for the
decompressor when building a 32-bit kernel.
Reported-and-tested-by: Chris Rankin <rankincj@yahoo.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
LKML-Reference: <219280.97558.qm@web52907.mail.re2.yahoo.com>
Diffstat (limited to 'arch/x86/boot')
| -rw-r--r-- | arch/x86/boot/compressed/Makefile | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index f8ed0658404c..f25bbd37765a 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile | |||
| @@ -9,6 +9,7 @@ targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinu | |||
| 9 | KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2 | 9 | KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2 |
| 10 | KBUILD_CFLAGS += -fno-strict-aliasing -fPIC | 10 | KBUILD_CFLAGS += -fno-strict-aliasing -fPIC |
| 11 | KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING | 11 | KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING |
| 12 | cflags-$(CONFIG_X86_32) := -march=i386 | ||
| 12 | cflags-$(CONFIG_X86_64) := -mcmodel=small | 13 | cflags-$(CONFIG_X86_64) := -mcmodel=small |
| 13 | KBUILD_CFLAGS += $(cflags-y) | 14 | KBUILD_CFLAGS += $(cflags-y) |
| 14 | KBUILD_CFLAGS += $(call cc-option,-ffreestanding) | 15 | KBUILD_CFLAGS += $(call cc-option,-ffreestanding) |