Subject: [RFC/PATCH v4 4/7] ARM: ARM11 MPCore: clean_dcache_area is not preempt safe

From: [email-masked] (Tony Lindgren)
Date: Tue, 18 Oct 2011 10:43:19 -0700

* George G. Davis <[email-masked]> [111018 09:56]:
> Hello Tony/Ohad,
> 
> On Oct 18, 2011, at 1:08 PM, Tony Lindgren wrote:
> 
> > Hi,
> > 
> > * gdavis at mvista.com <[email-masked]> [111018 06:13]:
> >> From: George G. Davis <[email-masked]>
> >> 
> >> If preemption and subsequent task migration occurs during calls to
> >> clean_dcache_area on ARM11 MPCore machines, global memory state
> >> can become inconsistent.  To prevent inconsistent memory state on
> >> these machines, disable preemption in callers of these functions
> >> around memory modifications and subsequent clean_dcache_area calls.
> > 
> > This one needs to be refreshed against what's queued in for-next as
> > Ohad has moved most of the iommu code into drivers. I've added
> > Ohad to Cc as well.
> 
> If you do not use ARM11 MPCore with those drivers, then we can drop this altogether.

No MPCore omaps available AFAIK, so that sounds OK to me.

Tony