How can I change cr0 register in redhat system

hi all:
       when I change the cr0 register I get a "Segmentation fault (core
dumped)".
       my code is :


.data
.text
.global _start
_start:
        movl %eax, %cr0

      this code can work well in ubuntu system when I use root to run it.
So what can I do to work it in redhat system?

     thanks
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