panic: Memory modified after free

[Doug White]

On Sat, 4 Feb 2006, Steve Kargl wrote:

> On Sat, Feb 04, 2006 at 09:51:32PM -0800, Doug White wrote:
> > Sorry for the late response on this, but I just debugged similar issues on
> > a Tyan S2892. The problem there was that the system would panic in unusual
> > places under load. The root cause was that the BIOS was not down-clocking
> > the DIMM speeds under high-load situations (e.g, all DIMM slots
> > populated), which caused random memory corruption. Updating to BIOS v2.00
> > fixed the problem.
> >
> > Make sure you are running BIOS v3.04 or later on your S2882.  The BIOS
> > download for that motherboard is:
> >
> > http://www.tyan.com/support/html/b_s2882.html
> >
> > The other option is to remove DIMMs from the system.
> >
>
> Updating the bios is the first thing I did.  IIRC, I'm at 3.05.
> The "Memory modified after free" is a real problem somewhere
> deep inside devfs.  See cognet's last commit to tty_pty.c.
>
> However, I'll look into the DIMM timing issues because I have
> been experiencing some lock-ups (not panics) when my system
> is under heavy load.  I've tested the memory with memtest86+
> more than once, and it appears to be good.

ok, if its reproducible, then I'll butt out. I wasted a week tracking the
bad memory timing issue, so tyan opteron problem nails are getting a whack
with my upgrade-BIOS hammer. :)

-- 
Doug White                    |  FreeBSD: The Power to Serve
dwhite at gumbysoft.com          |  www.FreeBSD.org