Hi,
 

That does not make much sense. Are you sure that you disassembled the
same binary which caused the general protection? I assume not.
 
 
Sorry! You are right, and I made a silly mistake.
 
It is an "int 0x80" instruction in lx_kill() in "lxfuxlibc/lib/src/lxfuxlc.c".
 
But I still think I am right at that the original cause. The backtrace is:
 
>main              // l4con/server/src/main.c
>do_switch
>vc_clear        // vc.c
>vc_fill
>pslim_fill        // pslim.c
>sw_fill
>vc->do_drty   // =  uxScreenUpdate   // con_hw/ux.c
>lx_kill             // lxfuxlibc/lib/src/lxfuxlc.c
>int 0x80
 
Regards,
 
Wei