On creation, the export's AioContext is set to the same one as the BlockBackend, while the AioContext in the client QIOChannel is left untouched.
As a result, when using data-plane, nbd_client_receive_next_request() schedules coroutines in the IOThread AioContext, while the client's QIOChannel is serviced from the main_loop, potentially triggering the assertion at qio_channel_restart_[read|write]. To fix this, as soon we have the export corresponding to the client, we call qio_channel_attach_aio_context() to attach the QIOChannel context to the export's AioContext. This matches with the logic in blk_aio_attached(). RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1748253 Signed-off-by: Sergio Lopez <s...@redhat.com> --- nbd/server.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/nbd/server.c b/nbd/server.c index 10faedcfc5..51322e2343 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -471,6 +471,7 @@ static int nbd_negotiate_handle_export_name(NBDClient *client, QTAILQ_INSERT_TAIL(&client->exp->clients, client, next); nbd_export_get(client->exp); nbd_check_meta_export(client); + qio_channel_attach_aio_context(client->ioc, client->exp->ctx); return 0; } @@ -673,6 +674,7 @@ static int nbd_negotiate_handle_info(NBDClient *client, uint16_t myflags, QTAILQ_INSERT_TAIL(&client->exp->clients, client, next); nbd_export_get(client->exp); nbd_check_meta_export(client); + qio_channel_attach_aio_context(client->ioc, exp->ctx); rc = 1; } return rc; -- 2.21.0
