Re: lockdep question (was Re: IPoIB caused a kernel: BUG: softlockup detected on CPU#0!)

[Ingo Molnar]

* Michael S. Tsirkin <mst@xxxxxxxxxxxxxx> wrote:

> > could you turn on CONFIG_SLAB_DEBUG as well?
> > 
> > that should catch certain types of use-after-free accesses, and 
> > lockdep will also warn if a still locked object is freed.
> 
> Hmm, no, this does not look like use-after-free. I enabled 
> CONFIG_SLAB_DEBUG, and I still see the same message, so the memory was 
> not overwritten by slab debugger.

that's still not conclusive - the memory might not have been allocated 
by slab again to detect it. Your magic-number check definitely shows 
some sort of corruption going on, right?

	Ingo
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