Re: port-alpha/41106: GENERIC.MP memory management faults on API CS20/HP DS20L

["Michael L. Hitch" <mhitch%lightning.msu.montana.edu@localhost>]

On Tue, 31 Mar 2009, dmarquess%gmail.com@localhost wrote:

> db{1}> bt
> cpu_Debugger() at netbsd:cpu_Debugger+0x4
> panic() at netbsd:panic+0x244
> trap() at netbsd:trap+0x35c
> XentMM() at netbsd:XentMM+0x20
> --- memory management fault (from ipl 5) ---
> uvm_pagealloc_strat() at netbsd:uvm_pagealloc_strat+0x64
...
> Problem does not occur with a GENERIC kernel, only GENERIC.MP

  It will also work with GENERIC.MP if you disable all the secondary cpus 
(which rather defeats the purpose of GENERIC.MP).

  I finally got a chance to start looking into this and found out that 
there's some per-cpu initialize going on before the secondary cpus are 
told they can start running.  Prior to that point, only the primary cpu 
has been added to the list of cpus, so the per-cpu setup doesn't occur on 
the secondary cpus.  I've got a fix for that, which at least lets me boot 
up and start running with multiple cpus, but eventually crashes later when 
it gets busy.  I'm in the process of trying to track that down now.

--
Michael L. Hitch                        mhitch%montana.edu@localhost
Computer Consultant
Information Technology Center
Montana State University        Bozeman, MT     USA