Re: lib/klist.c: bit 0 in pointer can't be used as flag

From: Jesper Nilsson
Date: Wed Jan 14 2009 - 05:20:29 EST


On Tue, Jan 13, 2009 at 11:45:21PM +0100, David Miller wrote:
> From: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
> Date: Wed, 14 Jan 2009 07:40:19 +0900
>
> > > It may be that we've worked around the other spots, although I haven't
> > > seen anything like that, we might just have been lucky until now.
> > >
> > > Can you recall another place where this trick is used?
> >
> > rmap.
> > Don't CRIS use mmu?
>
> I'm beginning to suspect the issue is only with objects
> in the kernel image itself. Dynamically allocated memory
> is properly aligned and therefore the "low bit status bits
> in pointer" trick works.

Yes, that agrees with what I see here, and why we haven't seen this
problem more often.

/^JN - Jesper Nilsson
--
Jesper Nilsson -- jesper.nilsson@xxxxxxxx
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