s390/kernel: build a relocatable kernel
This patch adds support for building a relocatable kernel with -fPIE.
The kernel will be relocated to 0 early in the boot process.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/Makefile b/arch/s390/Makefile
index 9c079a5..54b8a12 100644
--- a/arch/s390/Makefile
+++ b/arch/s390/Makefile
@@ -16,6 +16,10 @@
KBUILD_CFLAGS_MODULE += -fPIC
KBUILD_AFLAGS += -m64
KBUILD_CFLAGS += -m64
+ifeq ($(CONFIG_RELOCATABLE),y)
+KBUILD_CFLAGS += -fPIE
+LDFLAGS_vmlinux := -pie
+endif
aflags_dwarf := -Wa,-gdwarf-2
KBUILD_AFLAGS_DECOMPRESSOR := -m64 -D__ASSEMBLY__
KBUILD_AFLAGS_DECOMPRESSOR += $(if $(CONFIG_DEBUG_INFO),$(aflags_dwarf))
