On Mon, Jan 4, 2021 at 11:36 PM Nathan Chancellor
[off-list ref] wrote:

I am in agreement with Vlastimil, I would rather see the BUILD_BUG()
dropped or converted into BUG() instead of papering over with
__always_inline.

I see your point, but I also generally prefer build-time checks over
runtime ones wherever possible, and would prefer a way to keep
it in a form that allows that, at least if the check is considered useful
at all.

For what it's worth, I only see this build failure
with CONFIG_UBSAN_UNSIGNED_OVERFLOW, which you proposed disabling:

https://lore.kernel.org/lkml/20201230154749.746641-1-arnd@kernel.org/ (local)

I'm building more randconfig kernels without this patch but with the
__always_inline
reverted now, will see if it comes back. If not, let's just drop this patch.

      Arnd