Re: Do x86 NX and AMD prefetch check cause page fault infinite loop?

[Jamie Lokier]

Denis Vlasenko wrote:
> > This can only happen when something branches to a page with PROT_EXEC
> > _not_ set, on a kernel which honours that, and the target address is a
> > prefetch instruction.
> 
> Well. To be safe, just skip prefetch instruction, always.
> Hm. An attacker can supply us with whole gigabyte of
> prefetches back-to-back... Better skip all prefetches,
> with resheduling between every 1000 of them.

You could just skip one and return from the handler.
That's not a bad idea.

-- Jamie
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