[LTP] [RFC] [PATCH] lib: Add support for test tags

[Jan Stancek]

Hi,

----- Original Message -----
> This is just proof of concept of moving some of the test metadata into
> more structured form. If implemented it will move some information from
> comments in the test source code to an array to the tst_test structure.
> 
> It's not finished and certainly not set into a stone, this patch is
> mainly intended to start a discussion.
> 
> The newly introduced test tags are generic name-value pairs that can
> hold test metadata, the intended use for now is to store kernel commit
> hashes for kernel reproducers as well as CVE ids. The mechanism is
> however choosen to be very generic so that it's easy to add basically
> any information later on.
> 
> As it is the main purpose is to print hints for a test failures. If a
> test that has been written as a kernel reproducer fails it prints nice
> URL pointing to a kernel commit that may be missing.
> 
> Example output:
> 
> tst_test.c:1145: INFO: Timeout per run is 0h 05m 00s
> add_key02.c:98: FAIL: unexpected error with key type 'asymmetric': EINVAL
> add_key02.c:98: FAIL: unexpected error with key type 'cifs.idmap': EINVAL
> add_key02.c:98: FAIL: unexpected error with key type 'cifs.spnego': EINVAL
> add_key02.c:98: FAIL: unexpected error with key type 'pkcs7_test': EINVAL
> add_key02.c:98: FAIL: unexpected error with key type 'rxrpc': EINVAL
> add_key02.c:98: FAIL: unexpected error with key type 'rxrpc_s': EINVAL
> add_key02.c:98: FAIL: unexpected error with key type 'user': EINVAL
> add_key02.c:98: FAIL: unexpected error with key type 'logon': EINVAL
> 
> HINT: This is a regression test for linux kernel, see commit:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5649645d725c
> 
> HINT: This test also tests for CVE-2017-15274, see:
> 
> https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-15274
> 
> Summary:
> passed   0
> failed   8
> skipped  0
> warnings 0
> 
> This commit also adds adds the -q test flag, that can be used to query
> test information, which includes these tags, but is not limited to them.
> 
> The main inteded use for the query operation is to export test metadata
> and constraints to the test execution system. The long term goal for
> this would be parallel test execution as for this case the test runner
> would need to know which global system resources is the test using to
> avoid unexpected failures.
> 
> So far it exposes only if test needs root and if block device is needed
> for the test, but I would expect that we will need a few more tags for
> various resources, one that comes to my mind would be "test is using
> SystemV SHM" for that we can do something as add a "constraint" tag with
> value "SysV SHM" or anything else that would be fitting. Another would
> be "Test is changing system wide clocks", etc.
> 
> So far the output from the query operation looks as:
> 
> sh$ ./add_key02 -q
> {
>  "root": false
>  "blk_device": false
>  "linux-git": "5649645d725c"
>  "CVE": "2017-15274"
> }

So, only way to get metadata for tools is to run the test
with -q on supported target? (since I assume when
TST_TEST_TCONF branch hits, there won't be any data).

Would there be any benefit to having metadata in a (json)
file from the start? Negative would be likely duplicating
things like "needs_root". Positive is we could check for
errors/typos during build time.

Regards,
Jan

> 
> The format is meant to be machine-parseable, but it is certainly not
> final as there are no consumers for the data yet.
> 
> Another nice feature of having this information in the test runner is
> that we can include the URL pointing to a kernel git commit fixing the
> issue even for kernel reproducers that crashed the kernel under test and
> failed to write out any logs. Which is not that important I guess, but
> still nice to have.