Re: init does not run on 405GP system

[Denis Vlasenko]

On 10 June 2003 23:16, Robert Schwebel wrote:
> Hi,
> 
> I'm currently porting u-boot and Linux to an IBM 405GP based board. The
> problem is now that init seems not to be running and does not give any
> output. Up to that point where init should make some noise the kernel
> boots smoothly (serial console), I see all output and NFS-Root is
> mounted via an Intel 82559 network chip. The kernel threads are also
> running, I see kupdated & friends being put into the run queue from time
> to time.
> 
> I have replaced /sbin/init by a statically linked "hello world" (which
> also does not give any output). My impression is that the binary code of
> the init ELF binary is never run. When I switch on the SHOW_SYSCALLs
> macro in arch/ppc/kernel/entry.S I see the system calls for open(),
> dup(), dup() and execve() which come from init/main.c. Opening the
> console works, execve() to /sbin/init as well. When I follow the path of
> execution up to load_elf_binary() in fs/binfmt_elf.c I can even see the
> correct code being load and pointed to by elf_entry in that file. But
> there is never any output from init, nor does something happen when I
> replace init by a piece of code which should immediately make a zero
> pointer exception.
> 
> Nevertheless, the kernel runs smoothly. I can ping the machine, I can
> even floodping it with 0% packet loss. Only that there is no userspace
> running.
> 
> Has anybody seen something like this before?

Yes.

I once tried to run 686 based libc on a 486, init was rained upon
by SIGILLs 'coz it had 586+ instructions. No output on the screen
whatsoever.
--
vda