kpanic on install >32GB of RAM [SEC=UNCLASSIFIED]

[Sean Bruno]

On Fri, 2010-10-22 at 02:46 -0700, Ivan Voras wrote:
> On 10/21/10 21:06, Kostik Belousov wrote:
> > On Thu, Oct 21, 2010 at 09:50:03AM -0700, Sean Bruno wrote:
> >> On Thu, 2010-10-21 at 05:48 -0700, Andriy Gapon wrote:
> >>> on 20/10/2010 21:28 Sean Bruno said the following:
> >>>> I guess, I could replace the kernel on the CD and have them reburn it?
> >>>
> >>> That should work.
> >>> BTW, here I described "yet another" way of building custom recovery/installation
> >>> CDs that I use:
> >>> http://wiki.freebsd.org/AvgLiveCD
> >>>
> >>
> >> Before I get started on this, it looks like something else is going on.
> >>
> >> Here is a panic + trace on the latest 9-current snap shot.  "hammer
> >> time" indeed.  
> >>
> >> Suggestions are welcome!
> >>
> >>
> >> http://people.freebsd.org/~sbruno/9-current-panic.png
> >>
> >> http://people.freebsd.org/~sbruno/9-current-trace-panic.png
> > 
> > It feels like msgbufp variable has absurd value. Can you arrange
> > to get the output of verbose boot, esp. the SMAP lines ?
> 
> This is probably completely wrong for this problem but in the tiny case
> it isn't, maybe it will give someone an idea: I remember in the old
> times (tm) that there was a trick by which the msgbuf is supposed to be
> preserved across soft reboots. I don't know the details, and it might
> just be valid for i386 but part of that deal could be that some code
> tries to parse that memory area for valid msgbuf and due to some
> garbage, fails with such a panic.

Strange you should mention this.  Peter@ and I just had a 30 minute
driveway conversation about just this issue.

Sean