s390: introduce compile time check for empty .bss section

Introduce compile time check for files which should avoid using .bss
section, because of the following reasons:
- .bss section has not been zeroed yet,
- initrd has not been moved to a safe location and could be overlapping
with .bss section.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/arch/s390/scripts/Makefile.chkbss b/arch/s390/scripts/Makefile.chkbss
new file mode 100644
index 000000000000..d92f2d94a5d9
--- /dev/null
+++ b/arch/s390/scripts/Makefile.chkbss
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0
+
+quiet_cmd_chkbss = CHKBSS  $<
+define cmd_chkbss
+	if ! $(OBJDUMP) -j .bss -w -h $< | awk 'END { if ($$3) exit 1 }'; then \
+		echo "error: $< .bss section is not empty" >&2; exit 1; \
+	fi; \
+	touch $@;
+endef
+
+$(obj)/built-in.a: $(patsubst %, $(obj)/%.chkbss, $(chkbss))
+
+%.o.chkbss: %.o
+	$(call cmd,chkbss)