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SubjectRe: Memory problem with bttv driver
> > > > Yes.  Instead of remapping vmalloced kernel memory it gives you shared
> > > > anonymous pages, then does zerocopy DMA using kiobufs. You may run in
> > > > trouble with >4GB machines.
> > >
> > > Interesting.
> > > What's the problem on > 4GB ?
> >
> > The bt878/848 is a 32bit PCI device, it simply can't go DMA to main
> > memory above 4GB. At least on ia32, on architecures with a iommu
> > (sparc, ...) it should work without trouble.
>
> Sorry, maybe I should have clarified: what is the problem with allocating those
> pages below 4GB in a >4GB box?

do_anonymous_page() may give you pages above 4GB. Need to write my own
nopage handler to fix this.

Gerd

--
#define ENOCLUE 125 /* userland programmer induced race condition */
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