Re: [PATCH] selftests: kvm: fix mkdir error when building for non-supported arch

[Muhammad Usama Anjum <Usama.Anjum@collabora.com>]

Adding Sean

On 8/7/24 11:33 AM, Muhammad Usama Anjum wrote:
> On 8/7/24 11:08 AM, Muhammad Usama Anjum wrote:
>> On 8/6/24 9:00 PM, Shuah Khan wrote:
>>> On 8/6/24 06:10, Muhammad Usama Anjum wrote:
>>>> The mkdir generates an error when kvm suite is build for non-supported
>>>
>>> built
>>> unsupported
>>>
>>>> architecture such as arm. Fix it by ignoring the error from mkdir.
>>>>
>>>> mkdir: missing operand
>>>> Try 'mkdir --help' for more information.
>>>
>>> Simply suppressing the message isn't a good fix. Can you investigate
>>> a bit more on why mkdir is failing and the architectures it is failing
>>> on?
>>>
>>> This change simply suppresses the error message and continues - Should
>>> this error end the build process or not run mkdir to begin with by
>>> checking why $(sort $(dir $(TEST_GEN_PROGS)))) results in an empty
>>> string?
>> The tests are specified on per architecture basis. As KVM isn't supported on arm, there are no tests in TEST_GEN_PROGS and it is empty. While lib.mk infrastructure has support to ignore and not build anything in such cases, the Makefile's behaviour isn't robust enough.
>>
>> I think the better fix would be to check if TEST_GEN_PROGS isn't empty and then call mkdir. I'll reiterate and send the fix.
> 
> Waiting on Paolo's response before sending the following fix. Maybe he
> has better idea here.
> --- a/tools/testing/selftests/kvm/Makefile
> +++ b/tools/testing/selftests/kvm/Makefile
> @@ -317,7 +317,9 @@ $(LIBKVM_S_OBJ): $(OUTPUT)/%.o: %.S $(GEN_HDRS)
>  $(LIBKVM_STRING_OBJ): $(OUTPUT)/%.o: %.c
>  	$(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c -ffreestanding $< -o $@
> 
> -$(shell mkdir -p $(sort $(dir $(TEST_GEN_PROGS))))
> +ifneq ($(strip $(TEST_GEN_PROGS)),)
> +$(shell mkdir -p $(sort $(dir $(TEST_GEN_PROGS))))
> +endif
>  $(SPLIT_TEST_GEN_OBJ): $(GEN_HDRS)
>  $(TEST_GEN_PROGS): $(LIBKVM_OBJS)
>  $(TEST_GEN_PROGS_EXTENDED): $(LIBKVM_OBJS)
Do you agree with the fix or is there better fix? Please feel free to
jump in to propose better fix here.

> 
> 
>>
>>>
>>>>
>>>> Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
>>>> ---
>>>>   tools/testing/selftests/kvm/Makefile | 2 +-
>>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
>>>> index 48d32c5aa3eb7..8ff46a0a8d1cd 100644
>>>> --- a/tools/testing/selftests/kvm/Makefile
>>>> +++ b/tools/testing/selftests/kvm/Makefile
>>>> @@ -317,7 +317,7 @@ $(LIBKVM_S_OBJ): $(OUTPUT)/%.o: %.S $(GEN_HDRS)
>>>>   $(LIBKVM_STRING_OBJ): $(OUTPUT)/%.o: %.c
>>>>       $(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c -ffreestanding $< -o $@
>>>>   -$(shell mkdir -p $(sort $(dir $(TEST_GEN_PROGS))))
>>>> +$(shell mkdir -p $(sort $(dir $(TEST_GEN_PROGS))) > /dev/null 2>&1)
>>>>   $(SPLIT_TEST_GEN_OBJ): $(GEN_HDRS)
>>>>   $(TEST_GEN_PROGS): $(LIBKVM_OBJS)
>>>>   $(TEST_GEN_PROGS_EXTENDED): $(LIBKVM_OBJS)
>>>
>>>
>>> thanks,
>>> -- Shuah
>>
> 

-- 
BR,
Muhammad Usama Anjum