In <200103310715.CAA13322@sheffield.cnchost.com>
tad@entrisphere.com

> the first thing that cpu_startup() does is call
> 
> 	initmsgbuf((caddr_t)msgbuf_paddr, round_page(MSGBUFSIZE));
> 
> However a quick examination makes it appear as though msgbuf_paddr
> (which is in the bss segment) has never been initialized... Thus I

msgbuf_paddr is initialized in powerpc/powerpc/pmap.c:pmap_bootstrap(),
which is called from initppc() before cpu_startup() is called from main().

> It used to be at 0x3000.  Is there any particular reason why it moved?

msgbuf should be allocated on the higher physical pages to preserve
it during reboot and bootstrap.
---
Izumi Tsutsui
tsutsui@ceres.dti.ne.jp