Re: kernels built from netbsd-4 and netbsd-wrstuden-fixsa hang after loading (KERNBASE problem?)

["Greg A. Woods; Planix, Inc." <woods%planix.ca@localhost>]

On 18-Aug-08, at 12:13 PM, Greg A. Woods; Planix, Inc. wrote:

> I've just had a second kernel hang immediately after loading.


ARGH!  I think I found the problem....

Some time back I tried a recommended change to KERNBASE (setting it  
with 'options KERNBASE="0x80000000UL"') but somehow I never got around  
to testing it (probably because of constant crashing at the time), and  
now months later when I do "cvs update" to get other changes updated I  
forget about the untested config change.   Grrr.

OK, so, I think the crashes/hangs I've been hounded by for many months  
now (PR#s kern/37993 and kern/38019) are because of some kind of  
starvation of kva space (IIUC).  Some discussion I read some time ago  
suggested modifying KERNBASE to accommodate more kva space.  However  
if the adjusted kernel won't run, what else might I try?

(Clearly the underlying problem is that a resource starvation can  
result in a complete deadlock instead of just a degradation of service.)

I'll immediately try rebuilding without the KERNBASE change above and  
see if it'll boot again....

--
                                        Greg A. Woods; Planix, Inc.
                                        <woods%planix.ca@localhost>