Only use unshare to become root if we're actually going to use a scope

If the relevant environment variables are not set, scope_cmd() will
return an empty list and we won't use a scope after all. In that case
we don't need to use unshare either to become root and can rely on our
own become_root() function so check whether we're actually going to use
a scope or not.

diff --git a/mkosi/qemu.py b/mkosi/qemu.py
index bd1ddcf3f7ef7074175217a1014dcea6c6daf94d..058cbc1d85d45fdc86c5cdc8646904da2e7523cf 100644 (file)
--- a/mkosi/qemu.py
+++ b/mkosi/qemu.py
@@ -351,8 +351,9 @@ def start_virtiofsd(config: Config, directory: PathString, *, name: str, selinux
             gid = INVOKING_USER.gid if os.getgid() != INVOKING_USER.gid else None
             scope = scope_cmd(name=name, description=description, user=uid, group=gid)
         elif not uidmap and (os.getuid() == 0 or unshare_version() >= "2.38"):
-            runas = become_root_cmd()
             scope = scope_cmd(name=name, description=description)
+            if scope:
+                runas = become_root_cmd()
 
         with spawn(
             cmdline,