Re: panic in amap_wipeout (amd64)?

[Andrew Doran <ad%netbsd.org@localhost>]

On Wed, Jan 30, 2008 at 07:41:55PM +0000, Andrew Doran wrote:

> On Tue, Jan 29, 2008 at 08:01:43PM +0000, Steven M. Bellovin wrote:
> 
> > I need to gather a few more details before I send-pr, but is anyone
> > else seeing a reproducible panic in amap_wipeout?  I first noticed this
> > on a kernel from Friday, Jan 25 (amd64) on a Thinkpad T61.  If I boot
> > single-user and do
> 
> It could be a TLB management issue but it's more likely that something is
> corrupting memory. I've found this panic to be a sign that something is
> allocating memory with kmem_alloc() and then overrunning the allocation,
> or using it after freeing it. It could also happen if something calls
> kmem_free() on an area of kernel stack.

... I forgot to mention that I saw a report yesterday from an 8-cpu system
where the stack appears to be getting smashed for no apparent reason, and as
a result and the machine panics returning from interrupt.

Andrew