Re: [PATCH] clocksource: Avoid selecting mult values that mightoverflow when adjusted

From: Thomas Gleixner
Date: Thu Nov 03 2011 - 09:26:47 EST


On Thu, 3 Nov 2011, John Stultz wrote:
> On Thu, 2011-11-03 at 13:05 +0100, Thomas Gleixner wrote:
> > On Wed, 2 Nov 2011, John Stultz wrote:
> > >
> > > + WARN_ONCE(timekeeper.mult+adj >
> > > + timekeeper.clock->mult + timekeeper.clock->maxadj,
> > > + "Adjusting more then 11%%");
> >
> > Shouldn't we rather limit the update instead of just warn and overflow ?
>
> Well, I'm hesitant to commit to that, just yet. So I figured I'd start
> with the warning.

OTOH, we know right there that we might warp 32bit and confuse the
hell out of timekeeping, which is not a real good thing either.

Thanks,

tglx
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