I don't understand at all what you mean by "performed on the subject", but in the most natural interpretation, the sentence you gave is not passive. It is subject honorific form. And the sentence 明日の会議に行きませんか?
that you suggested will mean a different thing.
And although very unnatural, it is in principle possible to interpret your example as passive. In that case, it will not be a direct (ordinary) passive, but will be adversative (aka indirect) passive, meaning someone did something, which (often negatively) affected the subject. The standard way to literally translate this into English is to use on <subject>
.
雨に降られた
'{The rain fell/It rained} on me.'
'{The rain fell/It rained}, affecting me.'
二階の人にピアノを弾かれた
'The person on the second floor played the piano on me.'
'The person on the second floor played the piano, affecting me.'
So a very unnatural interpretation of your sentence as adversative passive will be like this:
明日の会議に行かれるんですか?
'Will the person go to tomorrow's meeting on you?'
'Will it be the case that you will be (negatively) affected due to the person's going to tomorrow's meeting?'