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You're reading from  Modern Computer Architecture and Organization – Second Edition - Second Edition

Product typeBook
Published inMay 2022
PublisherPackt
ISBN-139781803234519
Edition2nd Edition
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Author (1)
Jim Ledin
Jim Ledin
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Jim Ledin

Jim Ledin is the CEO of Ledin Engineering, Inc. Jim is an expert in embedded software and hardware design and testing. He is also an expert in system cybersecurity assessment and penetration testing. He has a B.S. degree in aerospace engineering from Iowa State University and an M.S. degree in electrical and computer engineering from the Georgia Institute of Technology. Jim is a registered professional electrical engineer in California, a Certified Information System Security Professional (CISSP), a Certified Ethical Hacker (CEH), and a Certified Penetration Tester (CPT).
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Privileged processor modes

Most operating systems running on 32-bit and 64-bit processors control access to system resources using the concept of privilege levels. The primary reasons for managing access in this manner are to enhance system stability, prevent unauthorized interactions with system hardware, and prevent unauthorized access to data.

Privileged execution improves system stability by ensuring only trusted code is allowed to execute instructions that provide unrestricted access to resources such as processor configuration registers and I/O devices. The operating system kernel and related modules, including device drivers, require privileged access to perform their functions. Because any crash of a kernel process or a device driver is likely to halt the entire system immediately, these software components generally undergo a careful design process and rigorous testing before being released for general use.

Running the operating system in a privileged context prevents...

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Modern Computer Architecture and Organization – Second Edition - Second Edition
Published in: May 2022Publisher: PacktISBN-13: 9781803234519

Author (1)

author image
Jim Ledin

Jim Ledin is the CEO of Ledin Engineering, Inc. Jim is an expert in embedded software and hardware design and testing. He is also an expert in system cybersecurity assessment and penetration testing. He has a B.S. degree in aerospace engineering from Iowa State University and an M.S. degree in electrical and computer engineering from the Georgia Institute of Technology. Jim is a registered professional electrical engineer in California, a Certified Information System Security Professional (CISSP), a Certified Ethical Hacker (CEH), and a Certified Penetration Tester (CPT).
Read more about Jim Ledin