[PATCH 01/11] Makefile: kselftest and kselftest-clean fail for make O=dir case

[Shuah Khan]

kselftest and kselftest-clean targets fail when object directory is
specified to relocate objects. Fix it so it can find the source tree
to build from.

make O=/tmp/kselftest_top kselftest

make[1]: Entering directory '/tmp/kselftest_top'
make[2]: Entering directory '/tmp/kselftest_top'
make[2]: *** tools/testing/selftests: No such file or directory.  Stop.
make[2]: Leaving directory '/tmp/kselftest_top'
./linux-kselftest/Makefile:1185: recipe for target
'kselftest' failed
make[1]: *** [kselftest] Error 2
make[1]: Leaving directory '/tmp/kselftest_top'
Makefile:145: recipe for target 'sub-make' failed
make: *** [sub-make] Error 2

Signed-off-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
---
 Makefile | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/Makefile b/Makefile
index eccb8d704c23..6a85322d0b3e 100644
--- a/Makefile
+++ b/Makefile
@@ -1180,13 +1180,18 @@ headers_check: headers_install
 # ---------------------------------------------------------------------------
 # Kernel selftest
 
+PHONY += __kselftest
+	kselftest_src := tools/testing/selftests
+	ifneq ($(KBUILD_SRC),)
+		kselftest_src := $(KBUILD_SRC)/tools/testing/selftests
+	endif
 PHONY += kselftest
-kselftest:
-	$(Q)$(MAKE) -C tools/testing/selftests run_tests
+kselftest: __kselftest
+	$(Q)$(MAKE) -C $(kselftest_src) run_tests
 
 PHONY += kselftest-clean
-kselftest-clean:
-	$(Q)$(MAKE) -C tools/testing/selftests clean
+kselftest-clean: __kselftest
+	$(Q)$(MAKE) -C $(kselftest_src) clean
 
 PHONY += kselftest-merge
 kselftest-merge:
-- 
2.11.0