On 8/15/23 11:31 AM, Pavel Begunkov wrote: > io_kiocb::cqe stores the completion info which we'll memcpy to > userspace, and we rely on callbacks and other later steps to populate > it with right values. We have never had problems with that, but it would > still be safer to zero it on allocation. > > Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx> > --- > io_uring/io_uring.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c > index e189158ebbdd..4d27655be3a6 100644 > --- a/io_uring/io_uring.c > +++ b/io_uring/io_uring.c > @@ -1056,7 +1056,7 @@ static void io_preinit_req(struct io_kiocb *req, struct io_ring_ctx *ctx) > req->link = NULL; > req->async_data = NULL; > /* not necessary, but safer to zero */ > - req->cqe.res = 0; > + memset(&req->cqe, 0, sizeof(req->cqe)); > } > > static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx, I think this is a good idea, but I wonder if we should open-clear it instead. I've had cases in the past where that's more efficient than calling memset. -- Jens Axboe
