ARM highmem stuff - 5687/1
Russell King - ARM Linux
linux at arm.linux.org.uk
Fri Sep 4 17:20:24 EDT 2009
On Fri, Sep 04, 2009 at 03:33:53PM -0400, Nicolas Pitre wrote:
> On Fri, 4 Sep 2009, Russell King - ARM Linux wrote:
> > In this case, flush_dcache_page() may just set the PG_dcache_dirty bit
> > without flushing anything.
> But only if there is indeed a mapping and it is unmapped. In which case
> isn't the flush going to happen before the page gets mapped into user
> space anyway?
Only if it still has a mapping at that point.
> > I do know that flush_anon_page() was required to stabilise the list server.
> Do you mean __cpuc_flush_dcache_page() inside flush_anon_page()?
I really don't know. flush_anon_page() wasn't written incrementally, it
was written to allow the accesses as described in cachetlb.txt to work as
expected. The rationale for this function is further described in commit
I really can't comment any further on this, and I'm really concerned
about changing the current behaviour. We know what we currently have
works, and given that we've lost a way to test changes in this area
anymore, I think it's definitely a case if leaving well alone.
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