[PATCH v2 0/2] kunit: add optional assertions to catch taint and lockdep warnings

[Malte Wechter <maltewechter@gmail.com>]

this patch tries to expand KUnit by using existing kernel diagnostics to
catch certain locking related bugs. Specifically this adds assertions for
`debug_locks` from `lockdep` and the `TAINT_WARN` flag from `panic`.
This tries to prevent bugs as: circular locking dependency and sleeping
function called from invalid context. 

Add config CONFIG_KUNIT_EXTRA_ASSERTS that enables extra assertions
to be emitted: First, before _any_ KUnit test suite is ran, this is to ensure
that the extra assertions are triggered by a KUnit test and not prior.
Secondly, assertions a made for each test case, failing them if the
assertions fail, even if the KUnit test is marked as passed.

Signed-off-by: Malte Wechter <maltewechter@gmail.com>
---
Changes in v2:
- Implement changes directly in C KUnit instead of Rust KUnit wrapper
- Remove rust specific configs and add general CONFIG_KUNIT_EXTRA_ASSERTS config
- Link to v1: https://patch.msgid.link/20260818-lockdep-kunit-v1-0-66ceb1a272e3@gmail.com

To: Brendan Higgins <brendan.higgins@linux.dev>
To: David Gow <david@davidgow.net>
To: Rae Moar <raemoar63@gmail.com>
To: Miguel Ojeda <ojeda@kernel.org>
To: Boqun Feng <boqun@kernel.org>
To: Gary Guo <gary@garyguo.net>
To: Björn Roy Baron <bjorn3_gh@protonmail.com>
To: Benno Lossin <lossin@kernel.org>
To: Andreas Hindborg <a.hindborg@kernel.org>
To: Alice Ryhl <aliceryhl@google.com>
To: Trevor Gross <tmgross@umich.edu>
To: Danilo Krummrich <dakr@kernel.org>
To: Daniel Almeida <daniel.almeida@collabora.com>
To: Tamir Duberstein <tamird@kernel.org>
To: Alexandre Courbot <acourbot@nvidia.com>
To: Onur Özkan <work@onurozkan.dev>
Cc: linux-kselftest@vger.kernel.org
Cc: kunit-dev@googlegroups.com
Cc: linux-kernel@vger.kernel.org
Cc: rust-for-linux@vger.kernel.org

---
Malte Wechter (2):
      kunit: add extra assertions to KUnit test cases
      kunit: add KUnit test to assert kernel state before KUnit suites are run

 lib/kunit/Kconfig     | 12 ++++++++++++
 lib/kunit/executor.c  |  8 +++++++-
 lib/kunit/test.c      | 30 ++++++++++++++++++++++++++++++
 lib/kunit/try-catch.c | 23 ++++++++++++++++++++++-
 4 files changed, 71 insertions(+), 2 deletions(-)
---
base-commit: 8cdeaa50eae8dad34885515f62559ee83e7e8dda
change-id: 20260812-lockdep-kunit-9628f4bcad90

Best regards,
--  
Malte Wechter <maltewechter@gmail.com>