No nuances, just buggy code (was: related to Spinlock implementation)
Maybe Linus should update the docs: <a href="https://www.kernel.org/doc/htmldocs/kernel-locking/locks.html" rel="nofollow">https://www.kernel.org/doc/htmldocs/kernel-locking/locks.htm...</a>
I think it would be useful to add a warning there.