20.3 Exploiting mainframe processor architecture

A unique feature of the mainframe is its processor architecture.

On the mainframe, you can address up to 2G in the 31-bit architecture. This is less than on other architectures. However, you do not have the kernel included in the user address space as you might have on other architectures (see Figure 20-1).

Figure 20-1. On the mainframe architecture, with 31-bit addressing, the kernel is in its own address space

graphics/20fig01.gif

The separation of the kernel from the user space results in additional security for the kernel. It is impossible for the user to access the kernel address space other than by system calls.



Linux on the Mainframe
Linux on the Mainframe
ISBN: 0131014153
EAN: 2147483647
Year: 2005
Pages: 199

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net