[ale] P5 bug

[Michael H. Warfield]

Chris Ricker enscribed thusly:
> On 12 Nov , Dave wrote:
> > I got an unconfirmed report that kernel 2.1.63 fixes the newly-discovered
> > P5 bug.
> > Can anyone else back this up?

	It does and the details of what it does and why it prevents it
were posted to BugTraq earlier today.  Seems to be a neat trick of arming
an illegal page table so that when that instruction gets hit it results
in a page trap before it has a chance to execute.  The kernel then has an
opportunity to deal with it.  Looks like Alan Cox figured it out from the
cryptic BSD announcement and came up with a solution of his own.  Aleph One
posted the pertainent parts of the 2.1.63 patch that fix the problem on
the BugTraq list as well.

> It seems to prevent the crash on my pentium.  I haven't benchmarked it
> yet to see how bad the damage is, though.

> later,
> chris

> --
> Chris Ricker                                 gt1355b at prism.gatech.edu

	Mike
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