Davies, 20, was a key member of the Bayern team which lifted the Champions League last season, but has been out with an ankle injury since October.
“He is back in the squad, all Bayern fans can look forward to that and it’s planned that he will play,” Bayern coach Hansi Flick said Tuesday.
However, he is short on options in defensive midfield.
Germany star Joshua Kimmich is out until at least January, while Corentin Tolisso is not yet fit, but may be ready for Saturday’s league game at FC Union Berlin.
Spain veteran Javi Martinez is also carrying a knock.
Bayern had their 15-match winning run in Europe ended last week when a weakened side drew 1-1 at Atletico Madrid.
Flick wants to finish the group stages with a win against a Moscow side who are bottom of the group and can not reach the last 16.
Bayern had to work hard to beat Lokomotiv 2-1 in Moscow in October when Kimmich grabbed the winner.
Flick says he expects the European champions to play “confidently” against Lokomotiv, who are without injured Russia striker Fyodor Smolov.