Before SQPOLL was transitioned to managing its own task_work, the core
used TWA_SIGNAL_NO_IPI to ensure that task_work was processed. If not,
we can't be sure that all task_work is processed at SQPOLL thread exit
time.
Fixes: af5d68f8892f ("io_uring/sqpoll: manage task_work privately")
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
        if (ctx->flags & IORING_SETUP_SQPOLL) {
                struct io_sq_data *sqd = ctx->sq_data;
 
-               if (wq_has_sleeper(&sqd->wait))
-                       wake_up(&sqd->wait);
+               if (sqd->thread)
+                       __set_notify_signal(sqd->thread);
                return;
        }