[PATCH 5.4 10/16] io_uring: always grab lock in io_cancel_async_work()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Jens Axboe <axboe@kernel.dk>

No upstream commit exists for this patch.

It's not necessarily safe to check the task_list locklessly, remove
this micro optimization and always grab task_lock before deeming it
empty.

Reported-and-tested-by: Lee Jones <lee@kernel.org>
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, 3 deletions(-)

--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3738,9 +3738,6 @@ static void io_cancel_async_work(struct
 {
 	struct io_kiocb *req;
 
-	if (list_empty(&ctx->task_list))
-		return;
-
 	spin_lock_irq(&ctx->task_lock);
 
 	list_for_each_entry(req, &ctx->task_list, task_list) {