Linux Libertine does not show Greek SmallCaps

Question

According to the Linux Libertine font tester you can have Greek small caps.

However the following example does not yield the desirable result:

\documentclass{article}
\usepackage{fontspec}
\setmainfont{Linux Libertine O}

\begin{document}
    \textsc{Small Capitals}
    \textsc{Πεζά κεφαλαία}
\end{document}

Output:

Answer 1

this should work:

\documentclass{article}% lualatex
\usepackage{fontspec}
\setmainfont[SmallCapsFont={LinLibertineOC},% fontname may be different
             SmallCapsFeatures={Letters=SmallCaps}]{Linux Libertine O}
\begin{document}
\textsc{Small Capitals}
\textsc{Πεζά κεφαλαία}
Πεζά κεφαλαία

\end{document}