diff --git a/gnu/services/base.scm b/gnu/services/base.scm
index 9bc78bd1aeae206ea01f00944b915c4d7506b854..bfe5f52af4a19e2b4607da9ec0e1f1aaefd812d9 100644
--- a/gnu/services/base.scm
+++ b/gnu/services/base.scm
@@ -137,6 +137,10 @@ (define* (file-system-service device target type
       (stop #~(lambda args
                 ;; Normally there are no processes left at this point, so
                 ;; TARGET can be safely unmounted.
+
+                ;; Make sure PID 1 doesn't keep TARGET busy.
+                (chdir "/")
+
                 (umount #$target)
                 #f))))))