Re: [PATCH v2] doc: kselftest: update for clarity on running kselftests in CI rings

From: shuah
Date: Thu Aug 29 2019 - 13:39:36 EST

On 8/29/19 11:30 AM, Brendan Higgins wrote:
On Mon, Aug 26, 2019 at 5:37 PM Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> wrote:

Update to add clarity and recommendations on running newer kselftests
on older kernels vs. matching the kernel and kselftest revisions.

The recommendation is "Match kernel revision and kselftest."

Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>

Reviewed-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>

One minor comment below.

Changes since v1: Fixed "WARNING: Title underline too short."

Documentation/dev-tools/kselftest.rst | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/Documentation/dev-tools/kselftest.rst b/Documentation/dev-tools/kselftest.rst
index 25604904fa6e..308506c5e8fa 100644
--- a/Documentation/dev-tools/kselftest.rst
+++ b/Documentation/dev-tools/kselftest.rst
@@ -12,6 +12,31 @@ write new tests using the framework on Kselftest wiki:

+Recommendations on running kselftests in Continuous Integration test rings
+It is recommended that users run Kselftest from the same release. Running
+newer Kselftest on older kernels isn't recommended for the following
+- Kselftest from mainline and linux-next might not be stable enough to run
+ on stable kernels.
+- Kselftests detect feature dependencies at run-time and skip tests if a
+ feature and/or configuration they test aren't enabled. Running newer
+ tests on older kernels could result in a few too many skipped/failed
+ conditions. It becomes difficult to evaluate the results.
+- Newer tests provide better coverage. However, users should make a judgement
+ call on coverage vs. run to run consistency and being able to compare
+ run to run results on older kernels.

I think this should be the "note" directive. You already have a list
of recommendations above; this seems like a TLDR section, or an
important note or tip.

+Match kernel revision and kselftest. Especially important for LTS and
+Stable kernel Continuous Integration test rings.
+Hot-plug tests
On some systems, hot-plug tests could hang forever waiting for cpu and
memory to be ready to be offlined. A special hot-plug target is created
to run the full range of hot-plug tests. In default mode, hot-plug tests run

Thanks Brendan. I am holding off on this patch for now. I will have
to make some updates. I will fold your comment in when I send an
updated patch.

-- Shuah