Re: [Qemu-devel] [PATCH v3 1/8] ahci-test: Add dependency to qemu-img tool

[John Snow <jsnow@redhat.com>]

On 2/7/19 1:51 PM, Thomas Huth wrote:
> On 2019-02-07 17:50, Philippe Mathieu-Daudé wrote:
>> On 2/5/19 1:18 AM, Philippe Mathieu-Daudé wrote:
>>> Since the ahci-test uses qemu-img, add a dependency to build it
>>> before using it.
>>> This fixes:
>>>
>>>   $ gmake check-qtest V=1
>>>   QTEST_QEMU_BINARY=x86_64-softmmu/qemu-system-x86_64 QTEST_QEMU_IMG=qemu-img tests/ahci-test
>>>   Failed to execute child process "/tmp/qemu-test.19tMRF/qemu-img" (No such file or directory)
>>>   ERROR:tests/libqos/libqos.c:192:mkimg: assertion failed: (ret && !err)
>>>
>>> Reviewed-by: John Snow <jsnow@redhat.com>
>>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>>> ---
>>> Slighly related is when vm-tests expect qemu-img available:
>>> https://lists.gnu.org/archive/html/qemu-devel/2018-06/msg08415.html
>>>
>>>   $ make vm-build-ubuntu.i386
>>>   Traceback (most recent call last):
>>>     File "source/qemu/tests/vm/basevm.py", line 236, in main
>>>       return vm.build_image(args.image)
>>>     File "tests/vm/ubuntu.i386", line 67, in build_image
>>>       subprocess.check_call(["qemu-img", "resize", img_tmp, "50G"])
>>>   OSError: [Errno 2] No such file or directory
>>>   tests/vm/Makefile.include:23: recipe for target 'tests/vm/ubuntu.i386.img' failed
>>>   make: *** [tests/vm/ubuntu.i386.img] Error 2
>>>
>>> A better fix would be checking those tools via ./configure...
>>> ---
>>>  tests/Makefile.include | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/tests/Makefile.include b/tests/Makefile.include
>>> index 75ad9c0dd3..679656b64a 100644
>>> --- a/tests/Makefile.include
>>> +++ b/tests/Makefile.include
>>> @@ -708,7 +708,7 @@ tests/prom-env-test$(EXESUF): tests/prom-env-test.o $(libqos-obj-y)
>>>  tests/rtas-test$(EXESUF): tests/rtas-test.o $(libqos-spapr-obj-y)
>>>  tests/fdc-test$(EXESUF): tests/fdc-test.o
>>>  tests/ide-test$(EXESUF): tests/ide-test.o $(libqos-pc-obj-y)
>>> -tests/ahci-test$(EXESUF): tests/ahci-test.o $(libqos-pc-obj-y)
>>> +tests/ahci-test$(EXESUF): tests/ahci-test.o $(libqos-pc-obj-y) qemu-img$(EXESUF)
>>
>> In [*] Cleber noticed if we configure using --disable-tools, qemu-img is
>> still built by when running "make check-block" due to this rule.
>>
>> I think this is OK because
>> - at least a test requires it, so this test will run (which is what
>>   we want)
>> - while the tool is available in the build directory, it still won't
>>   be installed by "make install"
> 
> I guess you could also introduce a CONFIG_TOOLS switch and only run the
> ahci test for CONFIG_TOOLS=y ? ... not that important, but in case you
> respin the series, maybe worth a try.
> 
>  Thomas
> 

Is this necessary?

You can run ahci-test by itself without building tools, but you need to
export QTEST_QEMU_IMG yourself, which you can absolutely point to some
other copy you have.

If you run "make check" though, it's going to use the built copy of
qemu-img no matter what, isn't it? so what's so great about preserving a
configuration where you ask it not to build tools and then intentionally
try to execute tests that will necessarily fail because they can't find
the qemu-img binary?

This seems fine the way it is, because you are asking the computer:

1. Not to build tools, please
2. Actually, please make the tools so I can run the tests


Convince me otherwise?
--js