Re: recent persistent boot failures

On Mon, 20 Feb 2012, Erik Bertelsen wrote:

> When booting recently built kernels (i.e. from sources after
> 2011-12-26) I have experienced boot failures like this:
> 
> Rebooting with command: boot
> Boot device: disk  File and args:
> NetBSD IEEE 1275 Bootblock
> >> NetBSD/sparc64 OpenFirmware Boot, Revision 1.10
> >> ([email protected], Sun Jul  8 02:00:04 CEST 2007)
> =0x414228
> Loading netbsd: 2303736+82408+182984=0x441330
> Fast Data Access MMU Miss
> ok boot netbsd.140
> 
> This happens both with kernels based on my custom configuration as
> well as GENERIC.
> 
> Any explanations? hw problems?

A "Fast Data Access MMU Miss" when before the kernel takes over the MMU 
from OpenBoot and the CPU tries to access a location that is not mapped 
into the firmware's page tables.  

I could speculate about what's causing the problem, but it's probably a 
better idea to do a "ctrace" and ".trap-registers" and try to diagnose the 
problem from there.

> Booting the kernel from 2011-12-26 (netbsd.140) consistently succeeds.

You can try to using CVS to move forward or backwrds over individual 
commits, but I don't see anything during that period that might be an 
obvious culprit.

Eduardo