Hi Pavel, and others...
As far as I can see io_send_zc_prep has this: if (unlikely(READ_ONCE(sqe->__pad2[0]) || READ_ONCE(sqe->addr3))) return -EINVAL; both are u64...Hah, true, completely forgot about that one
BTW: any comment on my "[RFC PATCH 0/8] cleanup struct io_uring_sqe layout" thread, that would make it much easier to figure out which fields are used..., see https://lore.kernel.org/io-uring/cover.1660291547.git.metze@xxxxxxxxx/#r metze
