From: Hao Xu <haoxu@linux.alibaba.com>
Date: Wed, 22 Sep 2021 10:12:37 +0000 (+0800)
Subject: io_uring: fix missing set of EPOLLONESHOT for CQ ring overflow
X-Git-Tag: v5.15.73~10870^2~13
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a62682f92eedb41c1cd8290fa875a4b85624fb9a;p=platform%2Fkernel%2Flinux-rpi.git

io_uring: fix missing set of EPOLLONESHOT for CQ ring overflow

We should set EPOLLONESHOT if cqring_fill_event() returns false since
io_poll_add() decides to put req or not by it.

Fixes: 5082620fb2ca ("io_uring: terminate multishot poll for CQ ring overflow")
Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20210922101238.7177-3-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 43530aae6180..ac0c06d5c629 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -5337,8 +5337,10 @@ static bool __io_poll_complete(struct io_kiocb *req, __poll_t mask)
 	}
 	if (req->poll.events & EPOLLONESHOT)
 		flags = 0;
-	if (!io_cqring_fill_event(ctx, req->user_data, error, flags))
+	if (!io_cqring_fill_event(ctx, req->user_data, error, flags)) {
+		req->poll.events |= EPOLLONESHOT;
 		flags = 0;
+	}
 	if (flags & IORING_CQE_F_MORE)
 		ctx->cq_extra++;