Re: NS83820 2.6.0-test5 driver seems unstable on IA64

[David Mosberger]

>>>>> On Sat, 27 Sep 2003 06:26:40 +0200, Andi Kleen <ak@xxxxxx> said:

  Andi> You handle misalignment->misalignment copies with zero or
  Andi> small cost - when both source and destination have the same
  Andi> misalignment. I guess you do that by just aligning the pointer
  Andi> at the beginning of the function. That works as long as both
  Andi> source and destination have the same misalignment.

  Andi> But that is not what happens here. The copy is a
  Andi> misaligned->aligned copy and that cannot be handled at zero
  Andi> cost (unless you have zero misalignment penalty in
  Andi> load/store). Either the load or the store in the copy loop
  Andi> will be always misaligned, no matter what tricks you play. You
  Andi> cannot avoid this by aligning the pointers.

Geez, Andi, get a clue.  You've been working with x86 for too long.

You really can't imagine that you could combine two source words into
a single destination word?  Look ma, no unaligned accesses...

	--david
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