[PATCH 5.10 15/54] io_uring: reinforce cancel on flush during exit

Greg Kroah-Hartman
2021-02-11T16:30:25Z

From: Pavel Begunkov <asml.silence@gmail.com>

[ Upstream commit 3a7efd1ad269ccaf9c1423364d97c9661ba6dafa ]

What 84965ff8a84f0 ("io_uring: if we see flush on exit, cancel related tasks")
really wants is to cancel all relevant REQ_F_INFLIGHT requests reliably.
That can be achieved by io_uring_cancel_files(), but we'll miss it
calling io_uring_cancel_task_requests(files=NULL) from io_uring_flush(),
because it will go through __io_uring_cancel_task_requests().

Just always call io_uring_cancel_files() during cancel, it's good enough
for now.

Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/io_uring.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -8692,10 +8692,9 @@ static void io_uring_cancel_task_request
io_cancel_defer_files(ctx, task, files);
io_cqring_overflow_flush(ctx, true, task, files);

+ io_uring_cancel_files(ctx, task, files);
if (!files)
__io_uring_cancel_task_requests(ctx, task);
- else
- io_uring_cancel_files(ctx, task, files);

if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
atomic_dec(&task->io_uring->in_idle);