Résume | Lusztig has given a construction of certain representations of reductive groups over finite local principal ideal rings of characteristic $p$, extending the construction of Deligne and Lusztig of representations of reductive groups over finite fields. We show how to generalize Lusztig's results to reductive groups over arbitrary finite local rings via the Greenberg functor and group schemes over Artinian local rings. In particular, we obtain a cohomological construction of a class of smooth representations of certain compact $p$-adic groups. |