On Wed, Sep 8, 2021 at 2:25 PM Brendan Higgins
[off-list ref] wrote:

I definitely agree that in the cases where KUnit is not actually
contributing to blowing the stack - struct leak just thinks it is,
this is fine; however, it sounds like Linus' concerns with KUnit's
macros go deeper than this.

I don't mind Kunit tests when they don't cause problems, but one very
natural way to use the Kunit test infrastructure does seem to be to
just put a lot of them into one function.

And then the individually fairly small structures just add up.
Probably mainly in some special configurations (ie together with
CONFIG_KASAN_STACK as pointed out by Arnd, but there might be other
cases that cause that issue too) where the compiler then doesn't merge
stack slots.

I wonder if those 'kunit_assert' structures could be split into two:
one part that could be 'static const', and at least shrink the dynamic
stack use that way. Because at a minimun, things like
type/file/line/format-msg seem to be things that really are just
static and const.

Hmm?

          Linus