ASM Segmentation Fault

Hey /prog/rammers,

I try to do a comparison between two strings, but I get a Segmentation Fault, can you guys help me to find the problem ?
Here is the code : http://pastebin.com/Ji2VGH6N

Thank you in advance.

>>3,5
It's also slow shit to use that 'repXX cmpsb' microcode. You're better off comparing (len % 8), ie (len & 7) bytes first, then comparing the rest of the strings as 64-bit segments at a time.