kbuild: fix generic asm-offsets.h support

iThis fixes a bug where the generated asm-offsets.h file was saved in
the source tree even with make O=.
Thanks to Stephen Rothwell <sfr@canb.auug.org.au> for the report.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

2 files changed, 4 insertions, 3 deletions

diff --git a/Kbuild b/Kbuild
index 1880e6f760aa..79003918f37f 100644
--- a/Kbuild
+++ b/Kbuild
@@ -4,7 +4,7 @@
 # 1) Generate asm-offsets.h
 
 #####
-# 1) Generate asm-offsets.h 
+# 1) Generate asm-offsets.h
 #
 
 offsets-file := include/asm-$(ARCH)/asm-offsets.h
@@ -22,6 +22,7 @@ sed-$(CONFIG_MIPS) := "/^@@@/s///p"
 
 quiet_cmd_offsets = GEN     $@
 define cmd_offsets
+        mkdir -p $(dir $@); \
         cat $< | \
         (set -e; \
          echo "#ifndef __ASM_OFFSETS_H__"; \
@@ -43,6 +44,6 @@ arch/$(ARCH)/kernel/asm-offsets.s: arch/$(ARCH)/kernel/asm-offsets.c FORCE
         $(Q)mkdir -p $(dir $@)
         $(call if_changed_dep,cc_s_c)
 
-$(srctree)/$(offsets-file): arch/$(ARCH)/kernel/asm-offsets.s Kbuild
+$(obj)/$(offsets-file): arch/$(ARCH)/kernel/asm-offsets.s Kbuild
         $(call cmd,offsets)
 
diff --git a/Makefile b/Makefile
index 524fb48fa334..382298f37adf 100644
--- a/Makefile
+++ b/Makefile
@@ -814,7 +814,7 @@ ifneq ($(KBUILD_MODULES),)
 endif
 
 prepare0: prepare prepare1 FORCE
-        $(Q)$(MAKE) $(build)=$(srctree)
+        $(Q)$(MAKE) $(build)=.
 
 # All the preparing..
 prepare-all: prepare0