Yes.  Interrupts are orthogonal to critical sections, including critical: blocks.  The only thing a critical: does is arrange that only one process can be executing it at any one time.  If you want uninterruptibility you'll want to use valueUninterruptibility.

(have you tried user interrupt again?)

 

So the real issue is what process the user interrupt action should interrupt.  For example, I think it's very wrong that the user interrupt action can interrupt the finalization process.  But which process it chooses is not well defined.  We've discussed this in the past without coming to much of a conclusion.