io_uring: fix __io_uring_files_cancel() with TASK_UNINTERRUPTIBLE

If the tctx inflight number haven't changed because of cancellation,
__io_uring_task_cancel() will continue leaving the task in
TASK_UNINTERRUPTIBLE state, that's not expected by
__io_uring_files_cancel(). Ensure we always call finish_wait() before
retrying.

Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2021-01-26 15:28:26 +00:00 committed by Jens Axboe
parent b18032bb0a
commit a1bb3cd589

View File

@ -9124,16 +9124,15 @@ void __io_uring_task_cancel(void)
prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
/*
* If we've seen completions, retry. This avoids a race where
* a completion comes in before we did prepare_to_wait().
* If we've seen completions, retry without waiting. This
* avoids a race where a completion comes in before we did
* prepare_to_wait().
*/
if (inflight != tctx_inflight(tctx))
continue;
schedule();
if (inflight == tctx_inflight(tctx))
schedule();
finish_wait(&tctx->wait, &wait);
} while (1);
finish_wait(&tctx->wait, &wait);
atomic_dec(&tctx->in_idle);
io_uring_remove_task_files(tctx);