io_uring: iopoll requests should also wake task ->in_idle state

If we're freeing/finishing iopoll requests, ensure we check if the task
is in idling in terms of cancelation. Otherwise we could end up waiting
forever in __io_uring_task_cancel() if the task has active iopoll
requests that need cancelation.

Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 985a9e3f976d3bf1e8b6da3aebbb6495fe875dc9..5cda878b69cfd038c9e29be8b526352f9b27b692 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2270,6 +2270,8 @@ static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
                struct io_uring_task *tctx = rb->task->io_uring;
 
                percpu_counter_sub(&tctx->inflight, rb->task_refs);
+               if (atomic_read(&tctx->in_idle))
+                       wake_up(&tctx->wait);
                put_task_struct_many(rb->task, rb->task_refs);
                rb->task = NULL;
        }
@@ -2288,6 +2290,8 @@ static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req)
                        struct io_uring_task *tctx = rb->task->io_uring;
 
                        percpu_counter_sub(&tctx->inflight, rb->task_refs);
+                       if (atomic_read(&tctx->in_idle))
+                               wake_up(&tctx->wait);
                        put_task_struct_many(rb->task, rb->task_refs);
                }
                rb->task = req->task;