From 2b246d533496d50c8fba1a42882668484e5984ac Mon Sep 17 00:00:00 2001
From: Albert ARIBAUD <albert.u.boot@aribaud.net>
Date: Tue, 11 Jun 2013 14:17:30 +0200
Subject: [PATCH] arm: ensure u-boot only uses relative relocations
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Add a Makefile target ('checkarmreloc') which
fails if the ELF binary contains relocation records
of types other than R_ARM_RELATIVE.

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
Tested-by: Lubomir Popov <lpopov@mm-sol.com>
Tested-by: Jeroen Hofstee <jeroen@myspectrum.nl>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
---
 Makefile           | 7 +++++++
 arch/arm/config.mk | 5 +++++
 2 files changed, 12 insertions(+)

diff --git a/Makefile b/Makefile
index 8dd09a55ca..dcb70ffa98 100644
--- a/Makefile
+++ b/Makefile
@@ -728,6 +728,13 @@ tools: $(VERSION_FILE) $(TIMESTAMP_FILE)
 	$(MAKE) -C $@ all
 endif	# config.mk
 
+# ARM relocations should all be R_ARM_RELATIVE.
+checkarmreloc: $(obj)u-boot
+	@if test "R_ARM_RELATIVE" != \
+		"`readelf -r $< | cut -d ' ' -f 4 | grep R_ARM | sort -u`"; \
+		then echo "$< contains relocations other than \
+		R_ARM_RELATIVE"; false; fi
+
 $(VERSION_FILE):
 		@mkdir -p $(dir $(VERSION_FILE))
 		@( localvers='$(shell $(TOPDIR)/tools/setlocalversion $(TOPDIR))' ; \
diff --git a/arch/arm/config.mk b/arch/arm/config.mk
index c43ebdd6f4..6479390b11 100644
--- a/arch/arm/config.mk
+++ b/arch/arm/config.mk
@@ -108,3 +108,8 @@ ifeq ($(GAS_BUG_12532),y)
 PLATFORM_RELFLAGS += -fno-optimize-sibling-calls
 endif
 endif
+
+# check that only R_ARM_RELATIVE relocations are generated
+ifneq ($(CONFIG_SPL_BUILD),y)
+ALL-y	+= checkarmreloc
+endif
-- 
2.39.2