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Re: [patch] rfa: fix problem with reassociating pointer additions


> > You'd think that, but the problem is in 64-bit processors with 32-bit
> > addressing in kernel mode.
> > 
> > I kid you not.
> > 
> > MIPS64TM Architecture For Programmers Volume III, Section 4.9.
> 
> After much fightingwith the MIPS web site, that section is:
> 4.9 Special Behavior for the kseg3 Segment when DebugDM = 1
> 
> I don't think that's what you meant.  Do you mean 4.10, which says:
>   prohibited from generating an effective address in which there is a
>   carry-out of bit 31. If such an address is produced,
>   the operation of the instruction generating such an address is
>   UNPREDICTABLE.
> 

Right part. Must've changed between versions. It's been a while since
I've downloaded it.

> If so, I don't see how that applies; the effective address produced
> will be properly sign extended.
> 
> I would need to see a test case...

I gave one in the thread...

-eric

-- 
Eric Christopher <echristo@redhat.com>


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