I would expect you'd get crashes if you had massive corruption in that
area. By default it's being used for the kernel pagetables, so stomping
on them will cause problems. In the cases we've been looking at so far,
it's only been a word or two being stomped.
The low 1Mbyte is used as general memory, so corruption over the whole
area will have widespread effects.
But try this patch (Hugh's version) and see what happens.
J
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