Consequences of hiding the NX/DX flag

I don't think there is any consequence of hiding this flag. It's not used for a performance boost but more towards security feature *CMIIW*

 

 

Taken from http://en.wikipedia.org/wiki/NX_bit :

 

 

NX/DX is used to mark certain areas of memory as non-executable so CPU will refuse to execute any code residing this area. This technique is used to prevent a malicious software from inserting their code into another program's data storage area and running their own code from within this section (aka. buffer overflow attack).