diff options
| author | Nathan Chancellor <nathan@kernel.org> | 2025-04-14 22:26:07 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2025-04-17 13:09:30 +0300 |
| commit | 498cb872a111e25021ca5e2d91af7b7a2e62630f (patch) | |
| tree | 282c0fc5abd074c38c9822910b91a83da0f05206 | |
| parent | 221df25fdf827b1fe5b904c6a396af06461a32f6 (diff) | |
| download | linux-498cb872a111e25021ca5e2d91af7b7a2e62630f.tar.xz | |
x86/boot/startup: Disable LTO for the startup code
When building with CONFIG_LTO_CLANG, there is an error in the x86 boot
startup code because it builds with a different code model than the rest
of the kernel:
ld.lld: error: Function Import: link error: linking module flags 'Code Model': IDs have conflicting values: 'i32 2' from vmlinux.a(head64.o at 1302448), and 'i32 1' from vmlinux.a(map_kernel.o at 1314208)
ld.lld: error: Function Import: link error: linking module flags 'Code Model': IDs have conflicting values: 'i32 2' from vmlinux.a(common.o at 1306108), and 'i32 1' from vmlinux.a(gdt_idt.o at 1314148)
As this directory is for code that only runs during early system
initialization, LTO is not very important, so filter out the LTO flags
from KBUILD_CFLAGS for arch/x86/boot/startup to resolve the build error.
Fixes: 4cecebf200ef ("x86/boot: Move the early GDT/IDT setup code into startup/")
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20250414-x86-boot-startup-lto-error-v1-1-7c8bed7c131c@kernel.org
Closes: https://lore.kernel.org/CA+G9fYvnun+bhYgtt425LWxzOmj+8Jf3ruKeYxQSx-F6U7aisg@mail.gmail.com/
| -rw-r--r-- | arch/x86/boot/startup/Makefile | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/boot/startup/Makefile b/arch/x86/boot/startup/Makefile index ccdfc42a4d59..bb7c826e586c 100644 --- a/arch/x86/boot/startup/Makefile +++ b/arch/x86/boot/startup/Makefile @@ -7,8 +7,9 @@ KBUILD_CFLAGS += -D__DISABLE_EXPORTS -mcmodel=small -fPIC \ -fno-stack-protector -D__NO_FORTIFY \ -include $(srctree)/include/linux/hidden.h -# disable ftrace hooks +# disable ftrace hooks and LTO KBUILD_CFLAGS := $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) +KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS)) KASAN_SANITIZE := n KCSAN_SANITIZE := n KMSAN_SANITIZE := n |