kbuild: disable depmod in cross-compile kernel build
When building embedded systems in a cross-compile environment and
populating a target's file system image, we don't want to run the
depmod on the host as we may be building for a completely different
architecture. Since there's no such thing as a cross-depmod, we
just disable running depmod in the cross-compile case and we just
run depmod on the target at bootup.
Inspired by patches from Christian, Armin and Deepak.
This solves: http://bugzilla.kernel.org/show_bug.cgi?id=3881
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Christian Bjølevik <nafallo@magicalforest.se>
Cc: Deepak Saxena <dsaxena@mvista.com> and
Cc: Armin Kuster <akuster@mvista.com>,
diff --git a/Makefile b/Makefile
index e8ace82..784903a6 100644
--- a/Makefile
+++ b/Makefile
@@ -1030,19 +1030,12 @@
fi
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
-# If System.map exists, run depmod. This deliberately does not have a
-# dependency on System.map since that would run the dependency tree on
-# vmlinux. This depmod is only for convenience to give the initial
+# This depmod is only for convenience to give the initial
# boot a modules.dep even before / is mounted read-write. However the
# boot script depmod is the master version.
-ifeq "$(strip $(INSTALL_MOD_PATH))" ""
-depmod_opts :=
-else
-depmod_opts := -b $(INSTALL_MOD_PATH) -r
-endif
PHONY += _modinst_post
_modinst_post: _modinst_
- if [ -r System.map -a -x $(DEPMOD) ]; then $(DEPMOD) -ae -F System.map $(depmod_opts) $(KERNELRELEASE); fi
+ $(call cmd,depmod)
else # CONFIG_MODULES
@@ -1259,15 +1252,6 @@
$(Q)mkdir -p $(MODLIB)/$(install-dir)
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
-# Run depmod only is we have System.map and depmod is executable
-quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
- cmd_depmod = if [ -r System.map -a -x $(DEPMOD) ]; then \
- $(DEPMOD) -ae -F System.map \
- $(if $(strip $(INSTALL_MOD_PATH)), \
- -b $(INSTALL_MOD_PATH) -r) \
- $(KERNELRELEASE); \
- fi
-
PHONY += _emodinst_post
_emodinst_post: _emodinst_
$(call cmd,depmod)
@@ -1516,6 +1500,16 @@
quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
cmd_rmfiles = rm -f $(rm-files)
+# Run depmod only is we have System.map and depmod is executable
+# and we build for the host arch
+quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
+ cmd_depmod = \
+ if [ -r System.map -a -x $(DEPMOD) -a "$(SUBARCH)" == "$(ARCH)" ]; then \
+ $(DEPMOD) -ae -F System.map \
+ $(if $(strip $(INSTALL_MOD_PATH)), -b $(INSTALL_MOD_PATH) -r) \
+ $(KERNELRELEASE); \
+ fi
+
a_flags = -Wp,-MD,$(depfile) $(KBUILD_AFLAGS) $(AFLAGS_KERNEL) \
$(NOSTDINC_FLAGS) $(KBUILD_CPPFLAGS) \