Re: kselftest: failed to build with -C tool/testing/selftests when KBUILD_OUTPUT is set

From: shuah <shuah@kernel.org>
To: Cristian Marussi <cristian.marussi@arm.com>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Tim.Bird@sony.com,
	"linux-kselftest@vger.kernel.org"
	<linux-kselftest@vger.kernel.org>, shuah <shuah@kernel.org>
Subject: Re: kselftest: failed to build with -C tool/testing/selftests when KBUILD_OUTPUT is set
Date: Wed, 27 Nov 2019 09:42:45 -0700	[thread overview]
Message-ID: <cf2ac53a-4547-0df7-52df-ef0ff4ffb453@kernel.org> (raw)
In-Reply-To: <c0d01c8f-1a40-e491-28e8-e93f8f90c874@arm.com>

On 11/27/19 9:23 AM, Cristian Marussi wrote:
> On 27/11/2019 16:04, shuah wrote:
>> On 11/27/19 3:54 AM, Cristian Marussi wrote:
>>> Hi
>>>
>>> On 27/11/2019 03:54, Michael Ellerman wrote:
>>>> Cristian Marussi <cristian.marussi@arm.com> writes:
>>>>> Hi
>>>>>
>>>>> while testing on linux-next
>>>>>
>>>>> I see that, when KBUILD_OUTPUT is set in the env, running something like (using TARGETS=exec as a random subsystem here...)
>>>>>
>>>>> $ make TARGETS=exec INSTALL_PATH=/nfs/LTP-official-debian-aarch64-rootfs/opt/KSFT_next kselftest-install
>>>>>
>>>>> works fine as usual, WHILE the alternative invocation (still documented in Documentation/dev-tools/kselftest.rst)
>>>>>
>>>>> make -C tools/testing/selftests/ TARGETS=exec INSTALL_PATH=/nfs/LTP-official-debian-aarch64-rootfs/opt/KSFT_next install
>>>>>
>>>>> fails miserably with:
>>>>> ...
>>>>> ...
>>>>>    REMOVE  usr/include/rdma/cxgb3-abi.h usr/include/rdma/nes-abi.h
>>>>>     HDRINST usr/include/asm/kvm.h
>>>>>     INSTALL /kselftest/usr/include
>>>>> mkdir: cannot create directory ‘/kselftest’: Permission denied
>>>>> /home/crimar01/ARM/dev/src/pdsw/linux/Makefile:1187: recipe for target 'headers_install' failed
>>>>> make[2]: *** [headers_install] Error 1
>>>>>
>>>>>
>>>>> This is fixed by unsetting KBUILD_OUTPUT OR reverting:
>>>>>
>>>>> 303e6218ecec (ksft/fixes) selftests: Fix O= and KBUILD_OUTPUT handling for relative paths
>>>>>
>>>>> since bypassing top makefile with -C, the definition of abs-objtree used by the above patch
>>>>> is no more available.
>>>>>
>>>>> As a side effect when KBUILD_OUTPUT is set, this breaks also the usage kselftest_install.sh.
>>>>>
>>>>>    $ ./kselftest_install.sh /home/crimar01/ARM/dev/nfs/LTP-official-debian-aarch64-rootfs/opt/KSFT_full_next
>>>>> ./kselftest_install.sh: Installing in specified location - /home/crimar01/ARM/dev/nfs/LTP-official-debian-aarch64-rootfs/opt/KSFT_full_next ...
>>>>> make --no-builtin-rules INSTALL_HDR_PATH=$BUILD/usr \
>>>>> 	ARCH=arm64 -C ../../.. headers_install
>>>>> make[1]: Entering directory '/home/crimar01/ARM/dev/src/pdsw/linux'
>>>>> make[2]: Entering directory '/home/crimar01/ARM/dev/src/pdsw/out_linux'
>>>>>     INSTALL /kselftest/usr/include
>>>>> mkdir: cannot create directory ‘/kselftest’: Permission denied
>>>>> /home/crimar01/ARM/dev/src/pdsw/linux/Makefile:1187: recipe for target 'headers_install' failed
>>>>> make[2]: *** [headers_install] Error 1
>>>>> make[2]: Leaving directory '/home/crimar01/ARM/dev/src/pdsw/out_linux'
>>>>> Makefile:179: recipe for target 'sub-make' failed
>>>>> make[1]: *** [sub-make] Error 2
>>>>> make[1]: Leaving directory '/home/crimar01/ARM/dev/src/pdsw/linux'
>>>>> Makefile:142: recipe for target 'khdr' failed
>>>>> make: *** [khdr] Error 2
>>>>>
>>>>>
>>>> ...
>>>>> Any thoughts ? ... or am I missing something ?
>>>>
>>>> You're not missing anything, this is broken.
>>> Thanks for the feedback !
>>>
>>> Cristian
>>>
>>>>
>>>>> (I think I'm starting to see this in latest CI linaro kselftest while they cross-compile for arm64)
>>>>
>>>> It just hit my travis jobs when I merged up to master:
>>>>
>>>>     https://travis-ci.org/linuxppc/linux/jobs/617482001
>>>>
>>>> Shuah can we please get this reverted?
>>>>
>>
>> I will take care of this. Supporting all these use-cases has been
>> maintenance problem. Fixing one use-case breaks another. :(
>>
>> I will look into fixing this once for all.
> 
> Thanks.
> 
> In fact all of the above works fine with the new kselftest-install target you added recently
> but I think a lot of CI is still using the old -C method.
> 
> Regards

If all of the above works with kselftest-install target, I would rather
ask for CI's to change, so we can get rid of make -C usage for install.

In which case, I would rather not revert this and request CIs to start
using kselftest-install target.

I would like to see CI's use kselftest-* targets from the main makefile
for build/run/install.

It has been very difficult to support "make -C" use-cases in general
and especially for install and relocatable builds.

thanks,
-- Shuah