Re: [PATCH 07/22] tests/acceptance/virtiofs_submounts.py: evaluate string not length

["Alex Bennée" <alex.bennee@linaro.org>]

Max Reitz <mreitz@redhat.com> writes:

> On 09.02.21 13:52, Alex Bennée wrote:
>> 
>> Max Reitz <mreitz@redhat.com> writes:
>> 
>>> On 09.02.21 12:24, Alex Bennée wrote:
>>>>
>>>> Max Reitz <mreitz@redhat.com> writes:
>>>>
>>>>> On 04.02.21 14:23, Alex Bennée wrote:
>>>>>>
>>>>>> Cleber Rosa <crosa@redhat.com> writes:
>>>>>>
>>>>>>> If the vmlinuz variable is set to anything that evaluates to True,
>>>>>>> then the respective arguments should be set.  If the variable contains
>>>>>>> an empty string, than it will evaluate to False, and the extra
>>>>>>> arguments will not be set.
>>>>>>>
>>>>>>> This keeps the same logic, but improves readability a bit.
>>>>>>>
>>>>>>> Signed-off-by: Cleber Rosa <crosa@redhat.com>
>>>>>>> ---
>>>>>>>     tests/acceptance/virtiofs_submounts.py | 2 +-
>>>>>>>     1 file changed, 1 insertion(+), 1 deletion(-)
>>>>>>>
>>>>>>> diff --git a/tests/acceptance/virtiofs_submounts.py b/tests/acceptance/virtiofs_submounts.py
>>>>>>> index f1b49f03bb..f25a386a19 100644
>>>>>>> --- a/tests/acceptance/virtiofs_submounts.py
>>>>>>> +++ b/tests/acceptance/virtiofs_submounts.py
>>>>>>> @@ -241,7 +241,7 @@ class VirtiofsSubmountsTest(BootLinux):
>>>>>>>     
>>>>>>>             super(VirtiofsSubmountsTest, self).setUp(pubkey)
>>>>>>>     
>>>>>>> -        if len(vmlinuz) > 0:
>>>>>>> +        if vmlinuz:
>>>>>>>                 self.vm.add_args('-kernel', vmlinuz,
>>>>>>>                                  '-append', 'console=ttyS0 root=/dev/sda1')
>>>>>>
>>>>>> And this is were I gave up because I can't see how to run the test:
>>>>>>
>>>>>>      ./tests/venv/bin/avocado run ./tests/acceptance/virtiofs_submounts.py
>>>>>>      JOB ID     : b3d9bfcfcd603189a471bec7d770fca3b50a81ee
>>>>>>      JOB LOG    : /home/alex/avocado/job-results/job-2021-02-04T13.21-b3d9bfc/job.log
>>>>>>       (1/5) ./tests/acceptance/virtiofs_submounts.py:VirtiofsSubmountsTest.test_pre_virtiofsd_set_up: CANCEL: vmlinuz parameter not set; you must point it to a Linux kernel binary to test (to run this test with the on-image kernel, set it to an empty string) (0.00 s)
>>>>>>       (2/5) ./tests/acceptance/virtiofs_submounts.py:VirtiofsSubmountsTest.test_pre_launch_set_up: CANCEL: vmlinuz parameter not set; you must point it to a Linux kernel binary to test (to run this test with the on-image kernel, set it to an empty string) (0.00 s)
>>>>>>       (3/5) ./tests/acceptance/virtiofs_submounts.py:VirtiofsSubmountsTest.test_post_launch_set_up: CANCEL: vmlinuz parameter not set; you must point it to a Linux kernel binary
>>>>>>      to test (to run this test with the on-image kernel, set it to an empty string) (0.00 s)
>>>>>>       (4/5) ./tests/acceptance/virtiofs_submounts.py:VirtiofsSubmountsTest.test_post_mount_set_up: CANCEL: vmlinuz parameter not set; you must point it to a Linux kernel binary to test (to run this test with the on-image kernel, set it to an empty string) (0.00 s)
>>>>>>       (5/5) ./tests/acceptance/virtiofs_submounts.py:VirtiofsSubmountsTest.test_two_runs: CANCEL: vmlinuz parameter not set; you must point it to a Linux kernel binary to test (to run this test with the on-image kernel, set it to an empty string) (0.00 s)
>>>>>>      RESULTS    : PASS 0 | ERROR 0 | FAIL 0 | SKIP 0 | WARN 0 | INTERRUPT 0 | CANCEL 5
>>>>>>      JOB TIME   : 0.56 s
>>>>>>
>>>>>> Given the test seems to make assumptions about an environment being
>>>>>> setup for it I think we need some documentation somewhere about what
>>>>>> those pre-requisites are.
>>>>>
>>>>> I find the cancel message pretty clear, but then again it was me who
>>>>> wrote it...
>>>>>
>>>>> Either you point the vmlinuz parameter to some Linux kernel you built
>>>>> yourself, or you set it to the empty string to just use the kernel
>>>>> that’s part of the image.  Setting Avocado parameters is done via -p,
>>>>> i.e. “-p key=value”.  So in this case
>>>>> “-p vmlinuz=/path/to/linux/build/arch/x86/boot/bzImage”, or
>>>>> “-p vmlinuz=''”.
>>>>>
>>>>> Ideally, vmlinuz='' would be the default, but there’s a problem with
>>>>> that: I submitted this test along with the patches that added the
>>>>> required feature to the Linux kernel, so at that point that feature was
>>>>> not part of Linux.  That’s why you generally have to point it to a Linux
>>>>> kernel binary you built yourself that has this feature (5.10 does).
>>>>
>>>> This is where it deviates from the rest of the check-acceptance tests.
>>>> Generally I don't have to worry about finding the right image myself.
>>>
>>> Yes, but there’s nothing I can do apart from just not having the test as
>>> part of qemu, which I don’t find better than to just cancel it when not
>>> run with the necessary parameters.
>> 
>> No I agree having the tests is useful.
>> 
>>>
>>> Or, well, I could let the test download and compile the Linux sources,
>>> but I don’t think that’s a viable alternative.
>> 
>> There has been discussion before but I agree it's not viable given the
>> compile times for such things.
>> 
>>>> At the least it would be worth pointing to a part of our docs on how
>>>> to build such an image.
>>>
>>> Well, I could perhaps come up with a comprehensive kernel configuration
>>> that works, but I really don’t think that’s valuable for people who just
>>> want to run the acceptance tests and don’t care about this test in
>>> particular.  I just don’t think they’re actually going to build a Linux
>>> kernel just for it.
>> 
>> Sure - but I was trying to review the series and as part of my review I
>> generally like to run the things I review. Hence why I stopped as I
>> couldn't get things running.
>> 
>>> (Alternatively, I could just build a Linux kernel here on my machine,
>>> upload the binary and point to it somewhere, e.g. in the cancel message.
>>>    That would be OK for me, and perhaps something I could imagine someone
>>> might actually use.)
>> 
>> I've actually done this with some Xen patches I'm working on at the
>> moment. I'll probably decorate the test with:
>> 
>>    @skipUnless(os.getenv('AVOCADO_ALLOW_UNTRUSTED_CODE'), 'untrusted code')
>> 
>> with a comment explaining what's waiting to be upstreamed. Once there
>> are upstream binaries I plan on transitioning the test to those.
>
> Oh, so you’d be fine with an in-code comment that explains why the 
> parameter is required right now, but will be optional in the future?  If 
> so, sounds good to me.

Yes that would be great ;-)

-- 
Alex Bennée