Re: [PATCH] Makefile: Fix separate output directory build of kselftests

[Shuah Khan <skhan@linuxfoundation.org>]

On 2/23/22 12:10 PM, Muhammad Usama Anjum wrote:
> Build of kselftests fail if kernel's top most Makefile is used for
> running or building kselftests with separate output directory. The
> absolute path is needed to reference other files during this kind of
> build. Set KBUILD_ABS_SRCTREE to use absolute path during the build. It
> fixes the following different types of errors:
> 
> make kselftest-all O=/linux_mainline/build
> Makefile:1080: ../scripts/Makefile.extrawarn: No such file or directory
> 
> make kselftest-all O=build
> Makefile:1080: ../scripts/Makefile.extrawarn: No such file or directory
> 
> Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
> ---
> I've tested this patch on top of next-20220217. The latest next-20220222
> have missing patches.

Can you give more details on the use-cases you tested? Did you test all
the ways kselftest are built?

> ---
>   Makefile | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/Makefile b/Makefile
> index 86f633c2809ea..62b3eb8a102ab 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1411,10 +1411,10 @@ tools/%: FORCE
>   
>   PHONY += kselftest
>   kselftest:
> -	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
> +	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests KBUILD_ABS_SRCTREE=1 run_tests
>   
>   kselftest-%: FORCE
> -	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
> +	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests KBUILD_ABS_SRCTREE=1 $*
>   
>   PHONY += kselftest-merge
>   kselftest-merge:
> 

Change looks good to me as long as all the supported use-cases work correctly.

Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>

thanks,
-- Shuah