On 6/7/25 01:52, Uros Bizjak wrote:

Let me reiterate what the patch brings to the table. It prevents
invalid references of per cpu variables to non-percpu locations.

Yes, it's a very useful mechanism. That's exactly why I want to preserve
it for developers or things like 0day that do build tests and don't care
about modules quadrupling in size.

Hiding these checks behind the CONFIG_EXPERT option breaks the
intention of the patch. IMO, it should be always enabled to avoid
errors, mentioned in the previous paragraph, already during the
development time.

I agree, it should always be enabled ... eventually. But now now. That's
why we're having this conversation: it's breaking too many things and
needs to be disabled.

I'm much more inclined to James' proposal. Maybe we can disable these
checks in v6.15 stable series, but leave them in v6.16? This would
leave a couple of months for distributions to update libbpf.

I'd be worried that it will hit a whole bunch of folks doing 6.16 work.
I was expecting to revert it _everywhere_ for now, if we go the revert
route.

James, by partial revert, did you mean to revert in stable but not
mainline? I assumed you meant to just revert patch 6/6 of the series
(stable and mainline) but leave 1-5 in place so turning it back on later
was easier.