IO_URING_PTR_POISON
req->ctx = IO_URING_PTR_POISON;
req->tctx = IO_URING_PTR_POISON;
req->file = IO_URING_PTR_POISON;
req->creds = IO_URING_PTR_POISON;
req->io_task_work.func = IO_URING_PTR_POISON;
req->apoll = IO_URING_PTR_POISON;
req->async_data = IO_URING_PTR_POISON;
req->kbuf = IO_URING_PTR_POISON;
req->comp_list.next = IO_URING_PTR_POISON;
req->file_node = IO_URING_PTR_POISON;
req->link = IO_URING_PTR_POISON;
mem->pages = IO_URING_PTR_POISON;
mem->sgt = IO_URING_PTR_POISON;
ifq->rq.ring = IO_URING_PTR_POISON;
ifq->rq.rqes = IO_URING_PTR_POISON;
ifq->notif_stats = IO_URING_PTR_POISON;