io_uring: don't attempt IO reissue from the ring exit path

If we're exiting the ring, just let the IO fail with -EAGAIN as nobody
will care anyway. It's not the right context to reissue from.

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

diff --git a/fs/io_uring.c b/fs/io_uring.c
index bf9ad810c621903882c555b1d67c5c31660da089..275ad84e8227b26604092d7493abb090b35cb80f 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2839,6 +2839,13 @@ static bool io_rw_reissue(struct io_kiocb *req)
                return false;
        if ((req->flags & REQ_F_NOWAIT) || io_wq_current_is_worker())
                return false;
+       /*
+        * If ref is dying, we might be running poll reap from the exit work.
+        * Don't attempt to reissue from that path, just let it fail with
+        * -EAGAIN.
+        */
+       if (percpu_ref_is_dying(&req->ctx->refs))
+               return false;
 
        lockdep_assert_held(&req->ctx->uring_lock);