Take the tour ×  I have a device that needs a block of memory
that is reserved solely for it, without the OS intervening. Is
there any way to tell BIOS or the OS that a block of memory is
reserved, and it must not use it?  I am using this device on an
openSUSE machine.  share|improve this question add comment  3
Answers  up vote 15 down vote accepted  What you're asking for
is called DMA. You need to write a driver to reserve this
memory.  Yes, I realize you said you didn't want the OS to
intervene, and a driver becomes part of the OS, but in absence
of a driver's reservation, the kernel believes all memory
belongs to it. (Unless you tell the kernel to ignore the memory
block, per Aaron's answer, that is.)  Chapter 15 (PDF) of "Linux
Device Drivers, 3/e" by Rubini, Corbet and Kroah-Hartmann covers
DMA and related topics.  If you want an HTML version of this, I
found the second-edition version of the chapter elsewhere
online. Beware that the 2nd edition is over a decade old now,
having come out when kernel 2.4