just the opposite -vort from Reb Shach -parshas behaloscha

Parshas Hashavua

?except or but  אלא 

Rashi ( 9:10 D.H. "או בדרך")

פסח שני מצה וחמץ עמו בבית"

ו                                                                                                                                      ואין איסר חמץ אלא עמו באכילתו" 

(There is no Issur Chometz except if eaten together

with the Korban)

The Minchas Chinuch asks on Rashi, "We don't

find anywhere in Chazal that there is an Issur to

eat the Korban Pesach Sheini  together with Chometz."

The Meshech Chochmo (Ohr Someiach) made up his

own Limmud, why it should be Assur to eat the Korban

together with Chametz.

Harav Shach zt"l said  Pshat in Rashi is just the opposite,

ואין איסר חמץ there is no Issur Chametz

"אלא עמו באכילתו"  = But you may eat Chometz together

with the Korban.