Merge tag 'io_uring-6.6-2023-10-06' of git://git.kernel.dk/linux

Pull io_uring fixes from Jens Axboe:

 - syzbot report on a crash on 32-bit arm with highmem, and went digging
   to check for potentially similar issues and found one more (me)

 - Fix a syzbot report with PROVE_LOCKING=y and setting up the ring in a
   disabled state (me)

 - Fix for race with CPU hotplut and io-wq init (Jeff)

* tag 'io_uring-6.6-2023-10-06' of git://git.kernel.dk/linux:
  io-wq: fully initialize wqe before calling cpuhp_state_add_instance_nocalls()
  io_uring: don't allow IORING_SETUP_NO_MMAP rings on highmem pages
  io_uring: ensure io_lockdep_assert_cq_locked() handles disabled rings
  io_uring/kbuf: don't allow registered buffer rings on highmem pages

1 files changed, 4 insertions, 6 deletions

diff --git a/io_uring/io-wq.c b/io_uring/io-wq.c
index 1ecc8c748768..522196dfb0ff 100644
--- a/io_uring/io-wq.c
+++ b/io_uring/io-wq.c
@@ -1151,9 +1151,6 @@ struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data)
 	wq = kzalloc(sizeof(struct io_wq), GFP_KERNEL);
 	if (!wq)
 		return ERR_PTR(-ENOMEM);
-	ret = cpuhp_state_add_instance_nocalls(io_wq_online, &wq->cpuhp_node);
-	if (ret)
-		goto err_wq;
 
 	refcount_inc(&data->hash->refs);
 	wq->hash = data->hash;
@@ -1186,13 +1183,14 @@ struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data)
 	wq->task = get_task_struct(data->task);
 	atomic_set(&wq->worker_refs, 1);
 	init_completion(&wq->worker_done);
+	ret = cpuhp_state_add_instance_nocalls(io_wq_online, &wq->cpuhp_node);
+	if (ret)
+		goto err;
+
 	return wq;
 err:
 	io_wq_put_hash(data->hash);
-	cpuhp_state_remove_instance_nocalls(io_wq_online, &wq->cpuhp_node);
-
 	free_cpumask_var(wq->cpu_mask);
-err_wq:
 	kfree(wq);
 	return ERR_PTR(ret);
 }