[PATCH] Subject: io_uring: Fix bug in io_fallback_req_func that can cause deadlock

[luhongfei]

There was a bug in io_fallback_req_func that can cause deadlocks
because uring_lock was not released when return.
This patch releases the uring_lock before return.

Signed-off-by: luhongfei <luhongfei@xxxxxxxx>
---
 io_uring/io_uring.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
 mode change 100644 => 100755 io_uring/io_uring.c

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 3bca7a79efda..1af793c7b3da
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -252,8 +252,10 @@ static __cold void io_fallback_req_func(struct work_struct *work)
 	mutex_lock(&ctx->uring_lock);
 	llist_for_each_entry_safe(req, tmp, node, io_task_work.node)
 		req->io_task_work.func(req, &ts);
-	if (WARN_ON_ONCE(!ts.locked))
+	if (WARN_ON_ONCE(!ts.locked)) {
+		mutex_unlock(&ctx->uring_lock);
 		return;
+	}
 	io_submit_flush_completions(ctx);
 	mutex_unlock(&ctx->uring_lock);
 }
-- 
2.39.0