x86/boot: kbuild: allow readelf executable to be specified

tpimh · masahir0y · commit eefb8c124fd9 · 2019-12-14T15:53:04.000+09:00
Introduce a new READELF variable to top-level Makefile, so the name of readelf binary can be specified. Before this change the name of the binary was hardcoded to "$(CROSS_COMPILE)readelf" which might not be present for every toolchain. This allows to build with LLVM Object Reader by using make parameter READELF=llvm-readelf. Link: ClangBuiltLinux#771 Signed-off-by: Dmitry Golovin <dima@golovin.in> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
diff --git a/Makefile b/Makefile
@@ -414,6 +414,7 @@ STRIP		= $(CROSS_COMPILE)strip
 OBJCOPY		= $(CROSS_COMPILE)objcopy
 OBJDUMP		= $(CROSS_COMPILE)objdump
 OBJSIZE		= $(CROSS_COMPILE)size
+READELF		= $(CROSS_COMPILE)readelf
 PAHOLE		= pahole
 LEX		= flex
 YACC		= bison
@@ -472,7 +473,7 @@ GCC_PLUGINS_CFLAGS :=
 CLANG_FLAGS :=
 
 export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
-export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE PAHOLE LEX YACC AWK INSTALLKERNEL
+export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
 export PERL PYTHON PYTHON2 PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
 
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
@@ -103,7 +103,7 @@ vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o
 quiet_cmd_check_data_rel = DATAREL $@
 define cmd_check_data_rel
 	for obj in $(filter %.o,$^); do \
-		${CROSS_COMPILE}readelf -S $$obj | grep -qF .rel.local && { \
+		$(READELF) -S $$obj | grep -qF .rel.local && { \
 			echo "error: $$obj has data relocations!" >&2; \
 			exit 1; \
 		} || true; \
