Merge branch 'io_uring-6.14' into for-6.15/io_uring

Merge mainline fixes into 6.15 branch, as upcoming patches depend on
fixes that went into the 6.14 mainline branch.

* io_uring-6.14:
  io_uring/net: save msg_control for compat
  io_uring/rw: clean up mshot forced sync mode
  io_uring/rw: move ki_complete init into prep
  io_uring/rw: don't directly use ki_complete
  io_uring/rw: forbid multishot async reads
  io_uring/rsrc: remove unused constants
  io_uring: fix spelling error in uapi io_uring.h
  io_uring: prevent opcode speculation
  io-wq: backoff when retrying worker creation

1 files changed, 18 insertions, 5 deletions

diff --git a/io_uring/io-wq.c b/io_uring/io-wq.c
index f7d328feb722..04a75d666195 100644
--- a/io_uring/io-wq.c
+++ b/io_uring/io-wq.c
@@ -63,7 +63,7 @@ struct io_worker {
 
 	union {
 		struct rcu_head rcu;
-		struct work_struct work;
+		struct delayed_work work;
 	};
 };
 
@@ -784,6 +784,18 @@ static inline bool io_should_retry_thread(struct io_worker *worker, long err)
 	}
 }
 
+static void queue_create_worker_retry(struct io_worker *worker)
+{
+	/*
+	 * We only bother retrying because there's a chance that the
+	 * failure to create a worker is due to some temporary condition
+	 * in the forking task (e.g. outstanding signal); give the task
+	 * some time to clear that condition.
+	 */
+	schedule_delayed_work(&worker->work,
+			      msecs_to_jiffies(worker->init_retries * 5));
+}
+
 static void create_worker_cont(struct callback_head *cb)
 {
 	struct io_worker *worker;
@@ -823,12 +835,13 @@ static void create_worker_cont(struct callback_head *cb)
 
 	/* re-create attempts grab a new worker ref, drop the existing one */
 	io_worker_release(worker);
-	schedule_work(&worker->work);
+	queue_create_worker_retry(worker);
 }
 
 static void io_workqueue_create(struct work_struct *work)
 {
-	struct io_worker *worker = container_of(work, struct io_worker, work);
+	struct io_worker *worker = container_of(work, struct io_worker,
+						work.work);
 	struct io_wq_acct *acct = io_wq_get_acct(worker);
 
 	if (!io_queue_worker_create(worker, acct, create_worker_cont))
@@ -866,8 +879,8 @@ fail:
 		kfree(worker);
 		goto fail;
 	} else {
-		INIT_WORK(&worker->work, io_workqueue_create);
-		schedule_work(&worker->work);
+		INIT_DELAYED_WORK(&worker->work, io_workqueue_create);
+		queue_create_worker_retry(worker);
 	}
 
 	return true;