Re: Promblem with PREF (prefetching) in memcpy

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

On Fri, 2002-10-04 at 14:00, Kevin D. Kissell wrote:
> The issue isn't that anyone would deliberately use memcpy() in I/O
> space.  Rather, it's that memcpy() prefetches quite a ways ahead,
> and if one has I/O space assigned just after the end of physical
> memory, Bad Things might happen on a perfectly legal memcpy()
> that references the last couple hundred bytes of memory in a 
> way that not even a clever and well-informed bus error handler 
> could undo.

Then your memcpy function is IMHO broken. Fix it to note prefetch beyond
the end of the area you actually will copy and life should be a lot
better