[PATCH 5/7] block/nbd: better document a case in nbd_co_establish_connection

[Roman Kagan]

Cosmetic: adjust the comment and the return value in
nbd_co_establish_connection where it's entered while the connection
thread is still running.

Signed-off-by: Roman Kagan <rvkagan@yandex-team.ru>
---
 block/nbd.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/block/nbd.c b/block/nbd.c
index a6d713ba58..a3eb9b9079 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -562,11 +562,12 @@ nbd_co_establish_connection(BlockDriverState *bs, Error 
**errp)
     case CONNECT_THREAD_RUNNING:
     case CONNECT_THREAD_RUNNING_DETACHED:
         /*
-         * Obviously, drained section wants to start. Report the attempt as
-         * failed. Still connect thread is executing in background, and its
+         * Spurious corotine resume before connection attempt has finished,
+         * presumably upon attaching a new aio_context. Report the attempt as
+         * failed.  Still connect thread is executing in background, and its
          * result may be used for next connection attempt.
          */
-        ret = -1;
+        ret = -ECONNABORTED;
         error_setg(errp, "Connection attempt cancelled by other operation");
         break;
 
-- 
2.30.2