From 58a2f7d85aaf4c41157f15c43a913b5c3c6b3adb Mon Sep 17 00:00:00 2001
From: Sam Ravnborg <sam@mars.ravnborg.org>
Date: Mon, 7 Aug 2006 20:58:28 +0200
Subject: [PATCH 1/2] kbuild: do not try to build content of initramfs

When a file supplied via CONFIG_INITRAMFS pointed to a file
for which kbuild had a rule to compile it (foo.c => foo.o)
then kbuild would compile the file before adding the
file to the initramfs.

Teach make that files included in initramfs shall not be updated by adding
an 'empty command'. (See "Using Empty Commands" in info make).

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
---
 usr/Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/usr/Makefile b/usr/Makefile
index e93824269da2..5b31c0b61c76 100644
--- a/usr/Makefile
+++ b/usr/Makefile
@@ -35,6 +35,9 @@ quiet_cmd_initfs = GEN     $@
       cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)
 
 targets := initramfs_data.cpio.gz
+# do not try to update files included in initramfs
+$(deps_initramfs): ;
+
 $(deps_initramfs): klibcdirs
 # We rebuild initramfs_data.cpio.gz if:
 # 1) Any included file is newer then initramfs_data.cpio.gz

From 9ee4e3365dd0dab4c1e02fe44dc08a223b826c72 Mon Sep 17 00:00:00 2001
From: Sam Ravnborg <sam@mars.ravnborg.org>
Date: Mon, 7 Aug 2006 21:01:36 +0200
Subject: [PATCH 2/2] kbuild: external modules shall not check config
 consistency

external modules needs include/linux/autoconf.h and include/config/auto.conf
but skip the integrity test of these. Even with a newer Kconfig file we
shall just proceed since external modules simply uses the kernel source and
shall not attempt to modify it.
Error out if a config fiel is missing since they are mandatory.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
---
 Makefile | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/Makefile b/Makefile
index 110db856e966..e71fefd220a7 100644
--- a/Makefile
+++ b/Makefile
@@ -436,12 +436,13 @@ core-y		:= usr/
 endif # KBUILD_EXTMOD
 
 ifeq ($(dot-config),1)
-# In this section, we need .config
+# Read in config
+-include include/config/auto.conf
 
+ifeq ($(KBUILD_EXTMOD),)
 # Read in dependencies to all Kconfig* files, make sure to run
 # oldconfig if changes are detected.
 -include include/config/auto.conf.cmd
--include include/config/auto.conf
 
 # To avoid any implicit rule to kick in, define an empty command
 $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
@@ -451,16 +452,27 @@ $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
 # if auto.conf.cmd is missing then we are probably in a cleaned tree so
 # we execute the config step to be sure to catch updated Kconfig files
 include/config/auto.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
-ifeq ($(KBUILD_EXTMOD),)
 	$(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
 else
-	$(error kernel configuration not valid - run 'make prepare' in $(srctree) to update it)
-endif
+# external modules needs include/linux/autoconf.h and include/config/auto.conf
+# but do not care if they are up-to-date. Use auto.conf to trigger the test
+PHONY += include/config/auto.conf
+
+include/config/auto.conf:
+	$(Q)test -e include/linux/autoconf.h -a -e $@ || (		\
+	echo;								\
+	echo "  ERROR: Kernel configuration is invalid.";		\
+	echo "         include/linux/autoconf.h or $@ are missing.";	\
+	echo "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
+	echo;								\
+	/bin/false)
+
+endif # KBUILD_EXTMOD
 
 else
 # Dummy target needed, because used as prerequisite
 include/config/auto.conf: ;
-endif
+endif # $(dot-config)
 
 # The all: target is the default when no target is given on the
 # command line.