Re: adjust prefetch in free_one_pgd()

David Woodhouse (dwmw2@infradead.org)
Sat, 03 Aug 2002 17:59:49 +0100

torvalds@transmeta.com said:
> > I thought the prefetches API intended this to be a safe operation?
> Well, any _sane_ prefetch API would be safe.
> However, there is known-broken hardware out there, in which a prefetch
> from IO space will kill the machine.

If you prefetch off the end of your object, and the thing you end up
prefetching is a DMA buffer which we'd just nuked from our cache to allow
the device to DMA into it, something's going to be unhappy regardless of
whether your prefetch faults or not.

--
dwmw2




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