Kernel Debugging

© Digital Equipment Corporation 1996
All Rights Reserved.

This manual explains how to use tools to debug a kernel and analyze a crash dump of the Digital UNIX operating system. Also, this manual explains how to write extensions to the kernel debugging tools.

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Restricted Rights: Use, duplication, or disclosure by the U.S. Government is subject to restrictions as set forth in subparagraph (c) (1) (ii).

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About This Manual

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Audience

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New and Changed Features

• Section 1.1, describing how to debug a kernel that is linked at bootstrap time, has been added.

• Section 2.1.2, describing how to debug images that are stripped of symbol table information, has been added.

• The new abscallout kdbx extension is explained in Section 2.2.3.4.

• Example 3-2, Example 3-4, andExample 3-5 have been updated.

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Organization

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Related Documents

• The Alpha Architecture Reference Manual describes how the operating system interfaces with the Alpha hardware.

• The Alpha Architecture Handbook gives an overview of the Alpha hardware architecture and describes the 64-bit Alpha RISC (Reduced Instruction Set Computing) instruction set.

• The Installation Guide describes how to install your operating system.

• The System Administration manual provides information on managing and monitoring your system.

• The Programmer's Guide provides information on the tools, specifically the dbx debugger, for programming on the Digital UNIX operating system. This manual also provides information about creating configurable kernel subsystems.

The printed version of the Digital UNIX documentation set is color coded to help specific audiences quickly find the books that meet their needs. (You can order the printed documentation from Digital.) This color coding is reinforced with the use of an icon on the spines of books. The following list describes this convention:

Some books in the documentation set help meet the needs of several audiences. For example, the information in some system books is also used by programmers. Keep this in mind when searching for information on specific topics.

The Documentation Overview, Glossary, and Master Index provides information on all of the books in the Digital UNIX documentation set.

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Conventions

%

$

A percent sign represents the C shell system prompt. A dollar sign represents the system prompt for the Bourne and Korn shells.

#

A number sign represents the superuser prompt.

% cat

Boldface type in interactive examples indicates typed user input.

file

Italic (slanted) type indicates variable values, placeholders, and function argument names.

[|]

{|}

In syntax definitions, brackets indicate items that are optional and braces indicate items that are required. Vertical bars separating items inside brackets or braces indicate that you choose one item from among those listed.

.
.
.

A vertical ellipsis indicates that a portion of an example that would normally be present is not shown.

cat(1)

A cross-reference to a reference page includes the appropriate section number in parentheses. For example, cat(1) indicates that you can find information on the cat command in Section 1 of the reference pages.

Ctrl/x

This symbol indicates that you hold down the first named key while pressing the key or mouse button that follows the slash. In examples, this key combination is enclosed in a box (for example, Ctrl/C).