On Wed, 2010-10-13 at 15:40 +0100, Mel Gorman wrote:

This is somewhat contrived but I can see how it might happen even on one
CPU particularly if the L1 cache is virtual and is loose about checking
physical tags.

quoted

How sensitive/vulnerable is PPC32 to such things?

I can not tell you specifically but if the above scenario is in any way
plausible, I believe it would depend on what sort of L1 cache the CPU
has. Maybe this particular version has a virtual cache with no physical
tagging and is depending on the OS not to make virtual aliasing mistakes.

Nah, ppc doesn't have problems with cache aliases, it all looks
physically tagged to the programmer (tho there's subtleties but none
that explains the reported behaviour).

Looks like real memory corruption to me.

Cheers,
Ben.