That is - precisely - the passive equivalent of she made me welcomeI was made welcome by her.
sounds a bit awkward, doesn't it ?
So you mean that with a long noun phrase that doesn't sound awkward ?Yes, it can be passivized, and 'I was made welcome by her' is correct. And yes, it sounds awkward, but I think that's because we don't usually put personal pronouns in the 'by'-phrase. It sounds better with a longer noun phrase: I was made welcome by the mistress of the house.