On Jul 23, 2012, at 9:32 AM, Fan Yang [off-list ref] wrote:

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?

Changing a control register is a privileged operation. You can't do it
from the user space. You can only do it from ring 0.

Venkatram Tummala

     thanks

_______________________________________________
Kernelnewbies mailing list
Kernelnewbies at kernelnewbies.org
http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies