kbuild: link-vmlinux.sh: Make output file name configurable

In order to introduce an intermediate, non-stripped vmlinux build that
can be used by other build steps as an input, pass the output file name
to link-vmlinux.sh via its command line.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Author: ardbiesheuvel

scripts/Makefile.vmlinux

@@ -69,7 +69,7 @@ ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
 
 # Final link of vmlinux with optional arch pass after final link
 cmd_link_vmlinux =							\
-	$< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";		\
+	$< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)" "$@";	\
 	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
 
 targets += vmlinux

scripts/link-vmlinux.sh

@@ -31,6 +31,7 @@ set -e
 LD="$1"
 KBUILD_LDFLAGS="$2"
 LDFLAGS_vmlinux="$3"
+VMLINUX="$4"
 
 is_enabled() {
 	grep -q "^$1=y" include/config/auto.conf
@@ -283,23 +284,23 @@ if is_enabled CONFIG_VMLINUX_MAP; then
 	generate_map=1
 fi
 
-vmlinux_link vmlinux
+vmlinux_link "${VMLINUX}"
 
 # fill in BTF IDs
 if is_enabled CONFIG_DEBUG_INFO_BTF; then
-	info BTFIDS vmlinux
+	info BTFIDS "${VMLINUX}"
 	RESOLVE_BTFIDS_ARGS=""
 	if is_enabled CONFIG_WERROR; then
 		RESOLVE_BTFIDS_ARGS=" --fatal_warnings "
 	fi
-	${RESOLVE_BTFIDS} ${RESOLVE_BTFIDS_ARGS} vmlinux
+	${RESOLVE_BTFIDS} ${RESOLVE_BTFIDS_ARGS} "${VMLINUX}"
 fi
 
-mksysmap vmlinux System.map
+mksysmap "${VMLINUX}" System.map
 
 if is_enabled CONFIG_BUILDTIME_TABLE_SORT; then
-	info SORTTAB vmlinux
-	if ! sorttable vmlinux; then
+	info SORTTAB "${VMLINUX}"
+	if ! sorttable "${VMLINUX}"; then
 		echo >&2 Failed to sort kernel tables
 		exit 1
 	fi
@@ -315,4 +316,4 @@ if is_enabled CONFIG_KALLSYMS; then
 fi
 
 # For fixdep
-echo "vmlinux: $0" > .vmlinux.d
+echo "${VMLINUX}: $0" > ".${VMLINUX}.d"