[PATCH] pci_alloc_consistent in an interrupt context

[Eugene Surovegin]

At 06:33 PM 6/13/2002, David Gibson wrote:
>On Thu, Jun 13, 2002 at 06:25:11PM -0700, Eugene Surovegin wrote:
> >
> > At 05:24 PM 6/13/2002, David Gibson wrote:
> > >That's right.  But I think the patch below is a better fix for the
> > >problem.  It makes consistent_alloc()/consistent_free() just do the
> > >right thing for both cache coherent and cache non-coherent processors,
> > >so we can get rid of the ifdef in pci_alloc_consistent() and
> > >pci_free_consistent().
> >
> > So, kmalloc will allocate non-cacheable memory?
> >
> > I seriously doubt it (actually I've just tested it:).
>
>No, but on cache coherent processors we don't need non-cacheable
>memory.  That's the whole point.  Likewise with __get_free_pages()
>which is what pci_alloc_consistent() uses on cache-coherent processors
>now.

OK, I got it :)

One problem though, kmalloc allocated memory will not be necessarily
properly aligned
as required by DMA-mappings.txt

Some PCI drivers may break because of this.

Eugene.


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