[PATCH v6 kspp-next 04/22] kbuild: merge vmlinux_link() between ARCH=um and other architectures

From: Alexander Lobakin <alexandr.lobakin@intel.com>
To: linux-hardening@vger.kernel.org
Cc: "Kristen C Accardi" <kristen.c.accardi@intel.com>,
	Kristen Carlson Accardi <kristen@linux.intel.com>,
	Kees Cook <keescook@chromium.org>,
	Masahiro Yamada <masahiroy@kernel.org>,
	"H. Peter Anvin" <hpa@zytor.com>, Jessica Yu <jeyu@kernel.org>,
	Nathan Chancellor <nathan@kernel.org>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Marios Pomonis <pomonis@google.com>,
	Sami Tolvanen <samitolvanen@google.com>,
	Tony Luck <tony.luck@intel.com>, Ard Biesheuvel <ardb@kernel.org>,
	Jesse Brandeburg <jesse.brandeburg@intel.com>,
	Lukasz Czapnik <lukasz.czapnik@intel.com>,
	"Marta A Plantykow" <marta.a.plantykow@intel.com>,
	Michal Kubiak <michal.kubiak@intel.com>,
	Michal Swiatkowski <michal.swiatkowski@intel.com>,
	Alexander Lobakin <alexandr.lobakin@intel.com>,
	linux-kbuild@vger.kernel.org, linux-arch@vger.kernel.org,
	linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com
Subject: [PATCH v6 kspp-next 04/22] kbuild: merge vmlinux_link() between ARCH=um and other architectures
Date: Tue, 31 Aug 2021 16:40:56 +0200	[thread overview]
Message-ID: <20210831144114.154-5-alexandr.lobakin@intel.com> (raw)
In-Reply-To: <20210831144114.154-1-alexandr.lobakin@intel.com>

From: Masahiro Yamada <masahiroy@kernel.org>

For ARCH=um, ${CC} is used as the linker driver. Hence, the linker
options are prefixed with -Wl, .

Merge the similar code.

I replaced the -T option with the long option --script= so that it
works well with/without ${wl}.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
---
 scripts/link-vmlinux.sh | 56 +++++++++++++++++------------------------
 1 file changed, 23 insertions(+), 33 deletions(-)

diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index 7b9c62e4d54a..d74cee5c4326 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -149,13 +149,12 @@ objtool_link()
 # ${2}, ${3}, ... - optional extra .o files
 vmlinux_link()
 {
-	local lds="${objtree}/${KBUILD_LDS}"
 	local output=${1}
-	local objects
-	local strip_debug
-	local map_option
 	local objs
 	local libs
+	local ld
+	local ldflags
+	local ldlibs
 
 	info LD ${output}
 
@@ -171,42 +170,33 @@ vmlinux_link()
 		libs="${KBUILD_VMLINUX_LIBS}"
 	fi
 
+	if [ "${SRCARCH}" = "um" ]; then
+		wl=-Wl,
+		ld="${CC}"
+		ldflags="${CFLAGS_vmlinux}"
+		ldlibs="-lutil -lrt -lpthread"
+	else
+		wl=
+		ld="${LD}"
+		ldflags="${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux}"
+		ldlibs=
+	fi
+
+	ldflags="${ldflags} ${wl}--script=${objtree}/${KBUILD_LDS}"
+
 	# The kallsyms linking does not need debug symbols included.
 	if [ "$output" != "${output#.tmp_vmlinux.kallsyms}" ] ; then
-		strip_debug=-Wl,--strip-debug
+		ldflags="${ldflags} ${wl}--strip-debug"
 	fi
 
 	if [ -n "${CONFIG_VMLINUX_MAP}" ]; then
-		map_option="-Map=${output}.map"
+		ldflags="${ldflags} ${wl}-Map=${output}.map"
 	fi
 
-	if [ "${SRCARCH}" != "um" ]; then
-		objects="--whole-archive ${objs} --no-whole-archive	\
-			 --start-group ${libs} --end-group		\
-			 $@"
-
-		${LD} ${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux}	\
-			${strip_debug#-Wl,}			\
-			-o ${output}				\
-			${map_option}				\
-			-T ${lds} ${objects}
-	else
-		objects="-Wl,--whole-archive			\
-			${KBUILD_VMLINUX_OBJS}			\
-			-Wl,--no-whole-archive			\
-			-Wl,--start-group			\
-			${KBUILD_VMLINUX_LIBS}			\
-			-Wl,--end-group				\
-			${@}"
-
-		${CC} ${CFLAGS_vmlinux}				\
-			${strip_debug}				\
-			-o ${output}				\
-			${map_option:+-Wl,${map_option}}	\
-			-Wl,-T,${lds}				\
-			${objects}				\
-			-lutil -lrt -lpthread
-	fi
+	${ld} ${ldflags} -o ${output}					\
+		${wl}--whole-archive ${objs} ${wl}--no-whole-archive	\
+		${wl}--start-group ${libs} ${wl}--end-group		\
+		$@ ${ldlibs}
 }
 
 # generate .BTF typeinfo from DWARF debuginfo
-- 
2.31.1

