Kernel Debugging
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Dm-X: Protecting Volume-Level Integrity for Cloud Volumes and Local
dm-x: Protecting Volume-level Integrity for Cloud Volumes and Local Block Devices Anrin Chakraborti Bhushan Jain Jan Kasiak Stony Brook University Stony Brook University & Stony Brook University UNC, Chapel Hill Tao Zhang Donald Porter Radu Sion Stony Brook University & Stony Brook University & Stony Brook University UNC, Chapel Hill UNC, Chapel Hill ABSTRACT on Amazon’s Virtual Private Cloud (VPC) [2] (which provides The verified boot feature in recent Android devices, which strong security guarantees through network isolation) store deploys dm-verity, has been overwhelmingly successful in elim- data on untrusted storage devices residing in the public cloud. inating the extremely popular Android smart phone rooting For example, Amazon VPC file systems, object stores, and movement [25]. Unfortunately, dm-verity integrity guarantees databases reside on virtual block devices in the Amazon are read-only and do not extend to writable volumes. Elastic Block Storage (EBS). This paper introduces a new device mapper, dm-x, that This allows numerous attack vectors for a malicious cloud efficiently (fast) and reliably (metadata journaling) assures provider/untrusted software running on the server. For in- volume-level integrity for entire, writable volumes. In a direct stance, to ensure SEC-mandated assurances of end-to-end disk setup, dm-x overheads are around 6-35% over ext4 on the integrity, banks need to guarantee that the external cloud raw volume while offering additional integrity guarantees. For storage service is unable to remove log entries documenting cloud storage (Amazon EBS), dm-x overheads are negligible. financial transactions. Yet, without integrity of the storage device, a malicious cloud storage service could remove logs of a coordinated attack. -
Troubleshooting Passwords
Troubleshooting Passwords The following procedures may be used to troubleshoot password problems: • Performing Password Recovery with an Existing Administrator, page 1 • Performing Password Recovery with No Existing Administrator, page 1 • Performing Password Recovery for the Linux Grapevine User Account, page 2 Performing Password Recovery with an Existing Administrator To perform password recovery for a user (administrator, installer or observer) where there exists at least one controller administrator (ROLE_ADMIN) user account, take the following steps: 1 Contact the existing administrator to set up a temporary password for the user that requires password recovery. Note The administrator can set up a temporary password by deleting the user's account and then recreating it with the lost password. The user can then log back into the controller to regain access and change the password once again to whatever he or she desires. 2 The user then needs to log into the controller with the temporary password and change the password. Note Passwords are changed in the controller GUI using the Change Password window. For information about changing passwords, see Chapter 4, Managing Users and Roles in the Cisco Application Policy Infrastructure Controller Enterprise Module Configuration Guide. Performing Password Recovery with No Existing Administrator The following procedure describes how to perform password recovery where there exists only one controller administrator (ROLE_ADMIN) user account and this account cannot be successfully logged into. Cisco Application Policy Infrastructure Controller Enterprise Module Troubleshooting Guide, Release 1.3.x 1 Troubleshooting Passwords Performing Password Recovery for the Linux Grapevine User Account Note We recommend that you create at least two administrator accounts for your deployment. -
Version 7.8-Systemd
Linux From Scratch Version 7.8-systemd Created by Gerard Beekmans Edited by Douglas R. Reno Linux From Scratch: Version 7.8-systemd by Created by Gerard Beekmans and Edited by Douglas R. Reno Copyright © 1999-2015 Gerard Beekmans Copyright © 1999-2015, Gerard Beekmans All rights reserved. This book is licensed under a Creative Commons License. Computer instructions may be extracted from the book under the MIT License. Linux® is a registered trademark of Linus Torvalds. Linux From Scratch - Version 7.8-systemd Table of Contents Preface .......................................................................................................................................................................... vii i. Foreword ............................................................................................................................................................. vii ii. Audience ............................................................................................................................................................ vii iii. LFS Target Architectures ................................................................................................................................ viii iv. LFS and Standards ............................................................................................................................................ ix v. Rationale for Packages in the Book .................................................................................................................... x vi. Prerequisites -
Linux for Zseries: Device Drivers and Installation Commands (March 4, 2002) Summary of Changes
Linux for zSeries Device Drivers and Installation Commands (March 4, 2002) Linux Kernel 2.4 LNUX-1103-07 Linux for zSeries Device Drivers and Installation Commands (March 4, 2002) Linux Kernel 2.4 LNUX-1103-07 Note Before using this document, be sure to read the information in “Notices” on page 207. Eighth Edition – (March 2002) This edition applies to the Linux for zSeries kernel 2.4 patch (made in September 2001) and to all subsequent releases and modifications until otherwise indicated in new editions. © Copyright International Business Machines Corporation 2000, 2002. All rights reserved. US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents Summary of changes .........v Chapter 5. Linux for zSeries Console || Edition 8 changes.............v device drivers............27 Edition 7 changes.............v Console features .............28 Edition 6 changes ............vi Console kernel parameter syntax .......28 Edition 5 changes ............vi Console kernel examples ..........28 Edition 4 changes ............vi Usingtheconsole............28 Edition 3 changes ............vii Console – Use of VInput ..........30 Edition 2 changes ............vii Console limitations ............31 About this book ...........ix Chapter 6. Channel attached tape How this book is organized .........ix device driver ............33 Who should read this book .........ix Tapedriverfeatures...........33 Assumptions..............ix Tape character device front-end........34 Tape block -
Xen and the Linux Console Or: Why Xencons={Tty,Ttys,Xvc} Will Go Away
Xen and the linux console or: why xencons={tty,ttyS,xvc} will go away. by Gerd Hoffmann <[email protected]> So, what is the Linux console? Well, there isn't a simple answer to that question. Which is the reason for this paper in the first place. For most users it probably is the screen they are sitting in front of. Which is correct, but it also isn't the full story. Especially there are a bunch of CONFIG_*_CONSOLE kernel options referring to two different (but related) subsystems of the kernel. Introducing virtual terminals (CONFIG_VT) Well, every linux user knows them: Virtual terminals. Using Alt-Fx you can switch between different terminals. Each terminal has its own device, namely /dev/tty<nr>. Most Linux distributions have a getty ready for text login on /dev/tty{1-6} and the X-Server for the graphical login on /dev/tty7. /dev/tty0 is a special case: It referes to the terminal which is visible at the moment. The VT subsystem doesn't draw the characters itself though, it has hardware specific drivers for that. The most frequently used ones are: CONFIG_VGA_CONSOLE VGA text console driver, this one will drive your VGA card if you boot the machine in VGA text mode. CONFIG_FRAMEBUFFER_CONSOLE Provides text screens on top of a graphical display. The graphical display in turn is driven by yet another driver. On x86 this very often is vesafb. Other platforms have generic drivers too. There are also a bunch of drivers for specific hardware, such as rivafb for nvidia cards. -
Operating System Support for Redundant Multithreading
Operating System Support for Redundant Multithreading Dissertation zur Erlangung des akademischen Grades Doktoringenieur (Dr.-Ing.) Vorgelegt an der Technischen Universität Dresden Fakultät Informatik Eingereicht von Dipl.-Inf. Björn Döbel geboren am 17. Dezember 1980 in Lauchhammer Betreuender Hochschullehrer: Prof. Dr. Hermann Härtig Technische Universität Dresden Gutachter: Prof. Frank Mueller, Ph.D. North Carolina State University Fachreferent: Prof. Dr. Christof Fetzer Technische Universität Dresden Statusvortrag: 29.02.2012 Eingereicht am: 21.08.2014 Verteidigt am: 25.11.2014 FÜR JAKOB *† 15. Februar 2013 Contents 1 Introduction 7 1.1 Hardware meets Soft Errors 8 1.2 An Operating System for Tolerating Soft Errors 9 1.3 Whom can you Rely on? 12 2 Why Do Transistors Fail And What Can Be Done About It? 15 2.1 Hardware Faults at the Transistor Level 15 2.2 Faults, Errors, and Failures – A Taxonomy 18 2.3 Manifestation of Hardware Faults 20 2.4 Existing Approaches to Tolerating Faults 25 2.5 Thesis Goals and Design Decisions 36 3 Redundant Multithreading as an Operating System Service 39 3.1 Architectural Overview 39 3.2 Process Replication 41 3.3 Tracking Externalization Events 42 3.4 Handling Replica System Calls 45 3.5 Managing Replica Memory 49 3.6 Managing Memory Shared with External Applications 57 3.7 Hardware-Induced Non-Determinism 63 3.8 Error Detection and Recovery 65 4 Can We Put the Concurrency Back Into Redundant Multithreading? 71 4.1 What is the Problem with Multithreaded Replication? 71 4.2 Can we make Multithreading -
MC-1200 Series Linux Software User's Manual
MC-1200 Series Linux Software User’s Manual Version 1.0, November 2020 www.moxa.com/product © 2020 Moxa Inc. All rights reserved. MC-1200 Series Linux Software User’s Manual The software described in this manual is furnished under a license agreement and may be used only in accordance with the terms of that agreement. Copyright Notice © 2020 Moxa Inc. All rights reserved. Trademarks The MOXA logo is a registered trademark of Moxa Inc. All other trademarks or registered marks in this manual belong to their respective manufacturers. Disclaimer Information in this document is subject to change without notice and does not represent a commitment on the part of Moxa. Moxa provides this document as is, without warranty of any kind, either expressed or implied, including, but not limited to, its particular purpose. Moxa reserves the right to make improvements and/or changes to this manual, or to the products and/or the programs described in this manual, at any time. Information provided in this manual is intended to be accurate and reliable. However, Moxa assumes no responsibility for its use, or for any infringements on the rights of third parties that may result from its use. This product might include unintentional technical or typographical errors. Changes are periodically made to the information herein to correct such errors, and these changes are incorporated into new editions of the publication. Technical Support Contact Information www.moxa.com/support Moxa Americas Moxa China (Shanghai office) Toll-free: 1-888-669-2872 Toll-free: 800-820-5036 Tel: +1-714-528-6777 Tel: +86-21-5258-9955 Fax: +1-714-528-6778 Fax: +86-21-5258-5505 Moxa Europe Moxa Asia-Pacific Tel: +49-89-3 70 03 99-0 Tel: +886-2-8919-1230 Fax: +49-89-3 70 03 99-99 Fax: +886-2-8919-1231 Moxa India Tel: +91-80-4172-9088 Fax: +91-80-4132-1045 Table of Contents 1. -
Linux Kernal II 9.1 Architecture
Page 1 of 7 Linux Kernal II 9.1 Architecture: The Linux kernel is a Unix-like operating system kernel used by a variety of operating systems based on it, which are usually in the form of Linux distributions. The Linux kernel is a prominent example of free and open source software. Programming language The Linux kernel is written in the version of the C programming language supported by GCC (which has introduced a number of extensions and changes to standard C), together with a number of short sections of code written in the assembly language (in GCC's "AT&T-style" syntax) of the target architecture. Because of the extensions to C it supports, GCC was for a long time the only compiler capable of correctly building the Linux kernel. Compiler compatibility GCC is the default compiler for the Linux kernel source. In 2004, Intel claimed to have modified the kernel so that its C compiler also was capable of compiling it. There was another such reported success in 2009 with a modified 2.6.22 version of the kernel. Since 2010, effort has been underway to build the Linux kernel with Clang, an alternative compiler for the C language; as of 12 April 2014, the official kernel could almost be compiled by Clang. The project dedicated to this effort is named LLVMLinxu after the LLVM compiler infrastructure upon which Clang is built. LLVMLinux does not aim to fork either the Linux kernel or the LLVM, therefore it is a meta-project composed of patches that are eventually submitted to the upstream projects. -
A Linux Kernel Scheduler Extension for Multi-Core Systems
A Linux Kernel Scheduler Extension For Multi-Core Systems Aleix Roca Nonell Master in Innovation and Research in Informatics (MIRI) specialized in High Performance Computing (HPC) Facultat d’informàtica de Barcelona (FIB) Universitat Politècnica de Catalunya Supervisor: Vicenç Beltran Querol Cosupervisor: Eduard Ayguadé Parra Presentation date: 25 October 2017 Abstract The Linux Kernel OS is a black box from the user-space point of view. In most cases, this is not a problem. However, for parallel high performance computing applications it can be a limitation. Such applications usually execute on top of a runtime system, itself executing on top of a general purpose kernel. Current runtime systems take care of getting the most of each system core by distributing work among the multiple CPUs of a machine but they are not aware of when one of their threads perform blocking calls (e.g. I/O operations). When such a blocking call happens, the processing core is stalled, leading to performance loss. In this thesis, it is presented the proof-of-concept of a Linux kernel extension denoted User Monitored Threads (UMT). The extension allows a user-space application to be notified of the blocking and unblocking of its threads, making it possible for a core to execute another worker thread while the other is blocked. An existing runtime system (namely Nanos6) is adapted, so that it takes advantage of the kernel extension. The whole prototype is tested on a synthetic benchmarks and an industry mock-up application. The analysis of the results shows, on the tested hardware and the appropriate conditions, a significant speedup improvement. -
Display Programming Guide
Serial text [Data] display Programming Guide [ Version 3.4 Firmware ] Issue 7 22 July 2014 This guide applies to the following models: BA488C - Panel mounted, Intrinsically Safe BA484D - Field mounted, Intrinsically Safe BA688C - Panel mounted, Safe Area BA684D - Field mounted, Safe Area Contents Introduction........................................................................................................................................................................1 What’s in this Programming Guide..............................................................................................................................1 What’s in the Instruction Manuals...............................................................................................................................1 What’s in the Modbus Interface Guide.........................................................................................................................1 Other sources of information........................................................................................................................................1 Enhanced Features........................................................................................................................................................2 Instrument Features...........................................................................................................................................................3 Display............................................................................................................................................................................3 -
ANSI® Programmer's Reference Manual Line Matrix Series Printers
ANSI® Programmer’s Reference Manual Line Matrix Series Printers Printronix, LLC makes no representations or warranties of any kind regarding this material, including, but not limited to, implied warranties of merchantability and fitness for a particular purpose. Printronix, LLC shall not be held responsible for errors contained herein or any omissions from this material or for any damages, whether direct, indirect, incidental or consequential, in connection with the furnishing, distribution, performance or use of this material. The information in this manual is subject to change without notice. This document contains proprietary information protected by copyright. No part of this document may be reproduced, copied, translated or incorporated in any other material in any form or by any means, whether manual, graphic, electronic, mechanical or otherwise, without the prior written consent of Printronix, LLC Copyright © 1998, 2012 Printronix, LLC All rights reserved. Trademark Acknowledgements ANSI is a registered trademark of American National Standards Institute, Inc. Centronics is a registered trademark of Genicom Corporation. Dataproducts is a registered trademark of Dataproducts Corporation. Epson is a registered trademark of Seiko Epson Corporation. IBM and Proprinter are registered trademarks and PC-DOS is a trademark of International Business Machines Corporation. MS-DOS is a registered trademark of Microsoft Corporation. Printronix, IGP, PGL, LinePrinter Plus, and PSA are registered trademarks of Printronix, LLC. QMS is a registered -
CP/M-80 Kaypro
$3.00 June-July 1985 . No. 24 TABLE OF CONTENTS C'ing Into Turbo Pascal ....................................... 4 Soldering: The First Steps. .. 36 Eight Inch Drives On The Kaypro .............................. 38 Kaypro BIOS Patch. .. 40 Alternative Power Supply For The Kaypro . .. 42 48 Lines On A BBI ........ .. 44 Adding An 8" SSSD Drive To A Morrow MD-2 ................... 50 Review: The Ztime-I .......................................... 55 BDOS Vectors (Mucking Around Inside CP1M) ................. 62 The Pascal Runoff 77 Regular Features The S-100 Bus 9 Technical Tips ........... 70 In The Public Domain... .. 13 Culture Corner. .. 76 C'ing Clearly ............ 16 The Xerox 820 Column ... 19 The Slicer Column ........ 24 Future Tense The KayproColumn ..... 33 Tidbits. .. .. 79 Pascal Procedures ........ 57 68000 Vrs. 80X86 .. ... 83 FORTH words 61 MSX In The USA . .. 84 On Your Own ........... 68 The Last Page ............ 88 NEW LOWER PRICES! NOW IN "UNKIT"* FORM TOO! "BIG BOARD II" 4 MHz Z80·A SINGLE BOARD COMPUTER WITH "SASI" HARD·DISK INTERFACE $795 ASSEMBLED & TESTED $545 "UNKIT"* $245 PC BOARD WITH 16 PARTS Jim Ferguson, the designer of the "Big Board" distributed by Digital SIZE: 8.75" X 15.5" Research Computers, has produced a stunning new computer that POWER: +5V @ 3A, +-12V @ 0.1A Cal-Tex Computers has been shipping for a year. Called "Big Board II", it has the following features: • "SASI" Interface for Winchester Disks Our "Big Board II" implements the Host portion of the "Shugart Associates Systems • 4 MHz Z80-A CPU and Peripheral Chips Interface." Adding a Winchester disk drive is no harder than attaching a floppy-disk The new Ferguson computer runs at 4 MHz.