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    SubjectRe: Does kmalloc always return address below 4GB?
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       From: Steffen Persvold <sp@scali.com>
    Date: Tue, 05 Mar 2002 16:43:01 +0100

    "David S. Miller" wrote:
    > Just use pci_alloc_consistent, it never gives you
    > anything larger than 32-bit addresses, please read the
    > documentation :-)

    What about memory for streaming mappings

    That's a different story.

    I know pci_map_single (and _sg) will
    use bounce buffers on platforms without an IOMMU,

    64-bit platforms without IOMMU use HIGHMEM.

    It could for example be solved with a GFP_32BIT flag or something (on IA64 I
    know GFP_DMA is used in pci_alloc_consistent() to get memory below 4GB but that
    can't be used on all platforms).

    IA64 was broken, it now uses HIGHMEM.

    Franks a lot,
    David S. Miller
    davem@redhat.com
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