regarding Linux booting

Hello,

This question is about linux booting
why is my board hangs after printing the message
"Freeing unused kernel memory: 48k init"
i have attached complete log in this mail.

I also checked the function init() (linux/init/main.c) it's hanging
in execve("/sbin/init",argv_init,envp_init).

But the strange thing is if i debug through
execve() -> sys_execve() ->do_execve the control comes out of
do_execve() and sys_execve(). but it hangs after that don't know why ?

any hint ?
where is execve() function in LINUX code for PPC based board.

NOTE:
We are booting LINUX on custom board having MPC8260 processor.

regards
shiva