2009-03-02 00:14:49     DMA Zone in kernel memory map

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2009-03-02 00:14:49     DMA Zone in kernel memory map

Sudhakar GN (INDIA)

Message: 70191   


Following is the memory map of my linux image:


Board Memory: 64MB

Kernel Managed Memory: 64MB

Memory map:

  text      = 0x00180000-0x002680f0

  rodata    = 0x00269000-0x002c3638

  data      = 0x002c4000-0x002d4000

    stack   = 0x002c4000-0x002c6000

  init      = 0x002d4000-0x004d4000

  bss       = 0x004d4000-0x00580fb8

  available = 0x00580fb8-0x03eff000

  DMA Zone  = 0x03f00000-0x04000000




My questiosn are:


Why is this " DMA Zone" required.


Is it possible to reduce or remove this memory? How?


Thanks in Advance,






2009-03-02 01:31:07     Re: DMA Zone in kernel memory map

Sonic Zhang (CHINA)

Message: 70194   


Some device drivers depend on uncached DMA memory to work. All other zones are cached memory.


You can adjust the size of DMA zone in kernenl configuration.