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Should I leave these as regular checks for now and add a > `TODO:` to use `unlikely()` once it is available? Regular checks are fine, no need for TODO either. Just bring this up to nud= ge Miguel to pick the patch :) > >> I wonder if we should upgrade this to `WARN_ONCE`. As code being execute= d when >> exiting are cleanup code, for this code path to be hit, it would mean th= at some >> code is installing FD descriptor while being dropped -- which is likely = a bug. >> >> Putting a "BTW, some Rust code is installing a FD when process is exitin= g" in >> dmesg is not going to be useful to understand what's going on. We'd want= a full >> backtrace. > > `WARN_ONCE` does not seem to be available on the Rust side yet either. > `warn_on!()` is available on the current base and would give us the > backtrace. Would you prefer using that here for now? I would prefer `warn_on!()`. Best, Gary > >> I think we can remove this warning. Skipping put_unused_fd isn't actuall= y >> leaking anything as the files_struct is cleaned up. > > Agreed. I'll treat dropping the reservation after fd table teardown as > normal cleanup, skip `put_unused_fd()`, and document that this can happen= . > > Best, > George