nixos X tests: wait for logind to link a session to the server

There seems to be some race causing failures if an X command gets in before slim starts the session

Signed-off-by: Shea Levy <shea@shealevy.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/nixos/lib/test-driver/Machine.pm b/nixos/lib/test-driver/Machine.pm
index a28214ea934f..8bef3d67b8d9 100644
--- a/nixos/lib/test-driver/Machine.pm
+++ b/nixos/lib/test-driver/Machine.pm
@@ -495,6 +495,8 @@ sub waitForX {
     my ($self, $regexp) = @_;
     $self->nest("waiting for the X11 server", sub {
         retry sub {
+            my ($status, $out) = $self->execute("journalctl -bu systemd-logind | grep Linked");
+            return 0 if $status != 0;
             my ($status, $out) = $self->execute("xwininfo -root > /dev/null 2>&1");
             return 1 if $status == 0;
         }