From: WANG Rui wangrui@loongson.cn
[ Upstream commit eea673e9d5ea994c60b550ffb684413d3759b3f4 ]
For the following assembly code:
.text .global func func: nop
.data var: .dword func
When linked with `-pie`, GNU LD populates the `var` variable with the pre-relocated value of `func`. However, LLVM LLD does not exhibit the same behavior. This issue also arises with the `kernel_entry` in arch/ loongarch/kernel/head.S:
_head: .word MZ_MAGIC /* "MZ", MS-DOS header */ .org 0x8 .dword kernel_entry /* Kernel entry point */
The correct kernel entry from the MS-DOS header is crucial for jumping to vmlinux from zboot. This necessity is why the compressed relocatable kernel compiled by Clang encounters difficulties in booting.
To address this problem, it is proposed to apply dynamic relocations to place with `--apply-dynamic-relocs`.
Link: https://github.com/ClangBuiltLinux/linux/issues/1962 Signed-off-by: WANG Rui wangrui@loongson.cn Signed-off-by: Huacai Chen chenhuacai@loongson.cn Signed-off-by: Sasha Levin sashal@kernel.org --- arch/loongarch/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile index fb0fada43197e..390867fc45b84 100644 --- a/arch/loongarch/Makefile +++ b/arch/loongarch/Makefile @@ -80,7 +80,7 @@ endif
ifeq ($(CONFIG_RELOCATABLE),y) KBUILD_CFLAGS_KERNEL += -fPIE -LDFLAGS_vmlinux += -static -pie --no-dynamic-linker -z notext +LDFLAGS_vmlinux += -static -pie --no-dynamic-linker -z notext $(call ld-option, --apply-dynamic-relocs) endif
cflags-y += $(call cc-option, -mno-check-zero-division)