In /proc/pid/maps grow-down VMA-s are shown without guard pages, but
sometime these "guard" pages can contain usefull data. For example if
a real guard page has been remmaped by another VMA. Let's call such
pages as fake guard pages.

So when a grow-down VMA is mmaped on restore, it should be mapped with
one more guard page to restore content of the fake guard page.

https://bugzilla.openvz.org/show_bug.cgi?id=2715Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>