Re: 2.6.17-rc2-mm1

[Andi Kleen]

On Wednesday 03 May 2006 09:08, Jan Beulich wrote:
> >> ><EOE>new stack 0 (0 0 0 10082 10)
> >> 
> >> Looks like <rubbish> <SS> <RSP> <RFLAGS> <CS> to me, ...
> >
> >Hmm, right.
> > 
> >> >Hmm weird. There isn't anything resembling an exception frame at the top of the
> >> >stack.  No idea how this could happen.
> >> 
> >> ... which is a valid frame where the stack pointer was corrupted before the exception occurred. One more printed
> item
> >> (or rather, starting items at estack_end[-1]) would allow at least seeing what RIP this came from.
> >
> >Any can you add that please and check? 
> ???

Sorry I meant to write Andy but left out the d :-( - he did the testing
on the machine that showed the problem.

> 

> 
> >Also worst case one could dump last branch pointers. AMD unfortunately only has four,
> >on Intel with 16 it's easier.
> 
> Provided you disable recording early enough. Otherwise only one (last exception from/to) is going to be useful on
> both.

i usually just saved them as first thing in the exception entry point.

> >That can cause recursive exceptions. I'm a bit paranoid with that.
> 
> Without doing so it can also cause recursive exceptions, just that this is going to be deadly then.

Hmm point.

-Andi

 
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