See also gnumach vm map entry forward merging.
IRC, freenode, #hurd, 2012-11-16
<mcsim> hi. do I understand correct that following is true: vm_object_t a; a->shadow->copy == a;? <braunr> mcsim: not completely sure, but i'd say no <braunr> but mach terminology isn't always firm, so possible <braunr> mcsim: apparently you're right, although be careful that it may not be the case *all* the time <braunr> there may be inconsistent states