From 108893ddcc4d3aa0a4a02aeb02d478e997001227 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Thu, 29 Sep 2022 22:23:19 +0100 Subject: [PATCH] io_uring/net: fix notif cqe reordering send zc is not restricted to !IO_URING_F_UNLOCKED anymore and so we can't use task-tw ordering trick to order notification cqes with requests completions. In this case leave it alone and let io_send_zc_cleanup() flush it. Cc: stable@vger.kernel.org Fixes: 53bdc88aac9a2 ("io_uring/notif: order notif vs send CQEs") Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/0031f3a00d492e814a4a0935a2029a46d9c9ba06.1664486545.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- io_uring/net.c | 24 +++++++++++++++++++----- 1 file changed, 19 insertions(+), 5 deletions(-) diff --git a/io_uring/net.c b/io_uring/net.c index 604eac5f7a34..caa6a803cb72 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -1127,8 +1127,14 @@ int io_send_zc(struct io_kiocb *req, unsigned int issue_flags) else if (zc->done_io) ret = zc->done_io; - io_notif_flush(zc->notif); - req->flags &= ~REQ_F_NEED_CLEANUP; + /* + * If we're in io-wq we can't rely on tw ordering guarantees, defer + * flushing notif to io_send_zc_cleanup() + */ + if (!(issue_flags & IO_URING_F_UNLOCKED)) { + io_notif_flush(zc->notif); + req->flags &= ~REQ_F_NEED_CLEANUP; + } io_req_set_res(req, ret, IORING_CQE_F_MORE); return IOU_OK; } @@ -1182,8 +1188,10 @@ int io_sendmsg_zc(struct io_kiocb *req, unsigned int issue_flags) req_set_fail(req); } /* fast path, check for non-NULL to avoid function call */ - if (kmsg->free_iov) + if (kmsg->free_iov) { kfree(kmsg->free_iov); + kmsg->free_iov = NULL; + } io_netmsg_recycle(req, issue_flags); if (ret >= 0) @@ -1191,8 +1199,14 @@ int io_sendmsg_zc(struct io_kiocb *req, unsigned int issue_flags) else if (sr->done_io) ret = sr->done_io; - io_notif_flush(sr->notif); - req->flags &= ~REQ_F_NEED_CLEANUP; + /* + * If we're in io-wq we can't rely on tw ordering guarantees, defer + * flushing notif to io_send_zc_cleanup() + */ + if (!(issue_flags & IO_URING_F_UNLOCKED)) { + io_notif_flush(sr->notif); + req->flags &= ~REQ_F_NEED_CLEANUP; + } io_req_set_res(req, ret, IORING_CQE_F_MORE); return IOU_OK; } -- 2.34.1