io_uring: ensure finish_wait() is always called in __io_uring_task_cancel()
authorJens Axboe <axboe@kernel.dk>
Fri, 15 Jan 2021 23:04:23 +0000 (16:04 -0700)
committerJens Axboe <axboe@kernel.dk>
Fri, 15 Jan 2021 23:04:23 +0000 (16:04 -0700)
If we enter with requests pending and performm cancelations, we'll have
a different inflight count before and after calling prepare_to_wait().
This causes the loop to restart. If we actually ended up canceling
everything, or everything completed in-between, then we'll break out
of the loop without calling finish_wait() on the waitqueue. This can
trigger a warning on exit_signals(), as we leave the task state in
TASK_UNINTERRUPTIBLE.

Put a finish_wait() after the loop to catch that case.

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

index 06cc79d..985a9e3 100644 (file)
@@ -9101,6 +9101,7 @@ void __io_uring_task_cancel(void)
                finish_wait(&tctx->wait, &wait);
        } while (1);
 
+       finish_wait(&tctx->wait, &wait);
        atomic_dec(&tctx->in_idle);
 
        io_uring_remove_task_files(tctx);