Hi, a friend and I were chasing bug 205219 [1] listed in Bugzilla. We step into something a little bit different when trying to reproduce the buggy behavior. In our try, compilation failed with a message form make asking us to clean the source tree. We couldn't run kunit_tool after compiling the kernel for x86, as described by Ted in the discussion pointed out by the bug report.
Steps to reproduce:
0) Run kunit_tool $ ./tools/testing/kunit/kunit.py run Works fine with a clean tree.
1) Compile the kernel for some architecture (we did it for x86_64).
2) Run kunit_tool again $ ./tools/testing/kunit/kunit.py run Fails with a message form make asking us to clean the source tree.
Removing the clean source tree check from the top-level Makefile gives us a similar error to what was described in the bug report. We see that after running `git clean -fdx` kunit_tool runs nicely again. However, this is not a real solution since some kernel binaries are erased by git.
We also had a look into the commit messages of Masahiro Yamada but couldn't quite grasp why the check for the tree to be clean was added. We could invest more time in this issue but actually don't know how to proceed. We'd be glad to receive any comment about it. We could also try something else if it's a too hard issue for beginners.
[1]: https://bugzilla.kernel.org/show_bug.cgi?id=205219
Best Regards,
Marcelo