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Subject[PATCH] x86/build: Keep local relocations with ld.lld
The LLVM linker (ld.lld) defaults to removing local relocations, which
causes KASLR boot failures. ld.bfd and ld.gold already handle this
correctly. This adds the explicit instruction "--discard-none" during
the link phase. There is no change in output for ld.bfd and ld.gold,
but ld.lld now produces an image with all the needed relocations.

Link: https://github.com/ClangBuiltLinux/linux/issues/404
Signed-off-by: Kees Cook <keescook@chromium.org>
---
arch/x86/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index a587805c6687..56e748a7679f 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -47,7 +47,7 @@ export REALMODE_CFLAGS
export BITS

ifdef CONFIG_X86_NEED_RELOCS
- LDFLAGS_vmlinux := --emit-relocs
+ LDFLAGS_vmlinux := --emit-relocs --discard-none
endif

#
--
2.17.1

--
Kees Cook

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