Re: Mystery packet killing tg3

[Peter Buckingham <peter@xxxxxxxxxxxx>]

Andi Kleen wrote:
> "David S. Miller" <davem@xxxxxxxxxxxxx> writes:
>
> > This usually means that there is some DMA corruption.
> > For example, some bug in the x86_64 IOMMU code or similar
> > causes a bogus DMA address to be fed to the tg3 or even
> > worse a DMA mapping is unmapped before tg3 is actually
> > done with it.
>
>
> IOMMU code on x86-64 should be never active unless Stephen
> used IOMMU_DEBUG or iommu=force.  THat is because the tg3
> is a 64bit capable device and should always use bypass.

how is this detected? we have a board that is using a 32bit e1000 and we 
have to use iommu=force otherwise it doesn't do the right thing with > 
4GB of RAM.

peter