Re: [Fdutils] DMA cache consistency bug introduced in 2.6.28

[Arjan van de Ven]

On Fri, 25 Dec 2009 21:33:04 +0100
Andi Kleen <andi@xxxxxxxxxxxxxx> wrote:

> On Fri, Dec 25, 2009 at 01:21:16PM +0100, Arjan van de Ven wrote:
> > On Wed, 23 Dec 2009 18:08:32 +0100
> > Andi Kleen <andi@xxxxxxxxxxxxxx> wrote:
> > 
> > > I removed that code when moving to 64bit (floppy driver disabling
> > > C1), but perhaps we need some variant of it again (but it's the
> > > first such report in many years). Although it would be sad to
> > > have it again on all systems.
> > 
> > at least now we have the pmqos infrastructure, driver just needs to
> > ask for 0 latency ;)
> 
> Does pmqos work with apci=off etc.? 

yes

> I didn't think it shut down
> the classic "HLT" idle, does it? 

it does if you specify a latency of 0; it will then go into the
spin-only state until you give up your latency requirement


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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