Allocating memory below 4G

From: Greg Law (glaw_at_nexwave-solutions.com)
Date: 04/15/05

  • Next message: Patrick Lam: "Screwed up rc.local, what can I do?" 
    Date: 15 Apr 2005 08:07:23 -0700

    Hi,

    I'm writing a driver for a device that requires DMA-able memory below
    4G. I'm running on an AMD x86_64 with 8GB RAM, and exausting the IOMMU
    entries. My device can't use bounce-buffers for performance reasons.
    So I'm kind-of stuck.

    Is there any way I can request the kernel give me physical memory below
    4G? I don't really want to insist on ZONE_NORMAL, since this is quite
    a limited resource, and I can quite happily have physical RAM in the 1G
    -> 4G range.

    Thanks in advance,

    Greg

  • Next message: Patrick Lam: "Screwed up rc.local, what can I do?"

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