90ac553bec
- Since polling should not involve sleeping, keep holding a process lock upon scanning file descriptors. - Hold a reference to every file descriptor prior to entering polling loop in order to avoid lock order reversal between lockmgr and p_mtx upon calling fdrop() in fo_poll(). (NOTE: this work has not been done for netncp and netsmb yet because a socket itself has no reference counts.) Reviewed by: jhb