diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2025-01-10 21:36:45 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-01-10 22:00:25 +0100 |
| commit | bd2703b42decebdcddf76e277ba76b4c4a142d73 (patch) | |
| tree | fb40c213c149d6bc89a6ca538b87ac07ce5491c6 /io_uring | |
| parent | io_uring/sqpoll: zero sqd->thread on tctx errors (diff) | |
| download | linux-bd2703b42decebdcddf76e277ba76b4c4a142d73.tar.xz linux-bd2703b42decebdcddf76e277ba76b4c4a142d73.zip | |
io_uring: don't touch sqd->thread off tw add
With IORING_SETUP_SQPOLL all requests are created by the SQPOLL task,
which means that req->task should always match sqd->thread. Since
accesses to sqd->thread should be separately protected, use req->task
in io_req_normal_work_add() instead.
Note, in the eyes of io_req_normal_work_add(), the SQPOLL task struct
is always pinned and alive, and sqd->thread can either be the task or
NULL. It's only problematic if the compiler decides to reload the value
after the null check, which is not so likely.
Cc: stable@vger.kernel.org
Cc: Bui Quang Minh <minhquangbui99@gmail.com>
Reported-by: lizetao <lizetao1@huawei.com>
Fixes: 78f9b61bd8e54 ("io_uring: wake SQPOLL task when task_work is added to an empty queue")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1cbbe72cf32c45a8fee96026463024cd8564a7d7.1736541357.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/io_uring.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index d3403c8216db..5eb119002099 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -1226,10 +1226,7 @@ static void io_req_normal_work_add(struct io_kiocb *req) /* SQPOLL doesn't need the task_work added, it'll run it itself */ if (ctx->flags & IORING_SETUP_SQPOLL) { - struct io_sq_data *sqd = ctx->sq_data; - - if (sqd->thread) - __set_notify_signal(sqd->thread); + __set_notify_signal(tctx->task); return; } |