On Wed, Oct 20, 2021 at 10:49:07AM -0600, Jens Axboe wrote: > It's not used for anything, and we're wasting time passing in zeroes > where we could just ignore it instead. Update all ki_complete users in > the kernel to drop that last argument. > > The exception is the USB gadget code, which passes in non-zero. But > since nobody every looks at ret2, it's still pointless. Yes, the USB gadget passes non-zero, and aio passes that on to userspace. So this is an ABI change. Does it actually matter? I don't know, but you could CC the relevant maintainers and list to try to figure that out.