d bus in the kernel
play

D-Bus in the Kernel FOSDEM 2014, Brussels, Belgium January 2014 - PowerPoint PPT Presentation

Jan 15, 2023 •138 likes •1.27k views

D-Bus in the Kernel FOSDEM 2014, Brussels, Belgium January 2014 D-Bus in the Kernel Who? Greg Kroah-Hartman, Daniel Mack, Lennart Poettering, Kay Sievers with help from Tejun Heo D-Bus in the Kernel Most newer OS designs started around

  1. kdbus Suitable for large data (GiB!), zero-copy, optionally reusable It’s efficient (2 or fewer copies, 2 validations, 2 context switches per duplex methd call transaction) Credentials sent along are comprehensive (uid, pid, gid, selinux label, pid starttime, tid, comm, tid comm, argv, exe, cgroup, caps, audit, . . . ) Implicit timestamping D-Bus in the Kernel

  2. kdbus Suitable for large data (GiB!), zero-copy, optionally reusable It’s efficient (2 or fewer copies, 2 validations, 2 context switches per duplex methd call transaction) Credentials sent along are comprehensive (uid, pid, gid, selinux label, pid starttime, tid, comm, tid comm, argv, exe, cgroup, caps, audit, . . . ) Implicit timestamping Always available, from earliest boot to latest shutdown D-Bus in the Kernel

  3. kdbus Suitable for large data (GiB!), zero-copy, optionally reusable It’s efficient (2 or fewer copies, 2 validations, 2 context switches per duplex methd call transaction) Credentials sent along are comprehensive (uid, pid, gid, selinux label, pid starttime, tid, comm, tid comm, argv, exe, cgroup, caps, audit, . . . ) Implicit timestamping Always available, from earliest boot to latest shutdown Open for LSMs to hook into from the kernel side D-Bus in the Kernel

  4. kdbus Suitable for large data (GiB!), zero-copy, optionally reusable It’s efficient (2 or fewer copies, 2 validations, 2 context switches per duplex methd call transaction) Credentials sent along are comprehensive (uid, pid, gid, selinux label, pid starttime, tid, comm, tid comm, argv, exe, cgroup, caps, audit, . . . ) Implicit timestamping Always available, from earliest boot to latest shutdown Open for LSMs to hook into from the kernel side Activation is identical to activation of other services D-Bus in the Kernel

  5. kdbus Suitable for large data (GiB!), zero-copy, optionally reusable It’s efficient (2 or fewer copies, 2 validations, 2 context switches per duplex methd call transaction) Credentials sent along are comprehensive (uid, pid, gid, selinux label, pid starttime, tid, comm, tid comm, argv, exe, cgroup, caps, audit, . . . ) Implicit timestamping Always available, from earliest boot to latest shutdown Open for LSMs to hook into from the kernel side Activation is identical to activation of other services Userspace is much simpler, no XML, . . . D-Bus in the Kernel

  6. kdbus Suitable for large data (GiB!), zero-copy, optionally reusable It’s efficient (2 or fewer copies, 2 validations, 2 context switches per duplex methd call transaction) Credentials sent along are comprehensive (uid, pid, gid, selinux label, pid starttime, tid, comm, tid comm, argv, exe, cgroup, caps, audit, . . . ) Implicit timestamping Always available, from earliest boot to latest shutdown Open for LSMs to hook into from the kernel side Activation is identical to activation of other services Userspace is much simpler, no XML, . . . Priority queues, . . . D-Bus in the Kernel

  7. kdbus Suitable for large data (GiB!), zero-copy, optionally reusable It’s efficient (2 or fewer copies, 2 validations, 2 context switches per duplex methd call transaction) Credentials sent along are comprehensive (uid, pid, gid, selinux label, pid starttime, tid, comm, tid comm, argv, exe, cgroup, caps, audit, . . . ) Implicit timestamping Always available, from earliest boot to latest shutdown Open for LSMs to hook into from the kernel side Activation is identical to activation of other services Userspace is much simpler, no XML, . . . Priority queues, . . . Race-free exit-on-idle for bus activated services D-Bus in the Kernel

  8. kdbus Suitable for large data (GiB!), zero-copy, optionally reusable It’s efficient (2 or fewer copies, 2 validations, 2 context switches per duplex methd call transaction) Credentials sent along are comprehensive (uid, pid, gid, selinux label, pid starttime, tid, comm, tid comm, argv, exe, cgroup, caps, audit, . . . ) Implicit timestamping Always available, from earliest boot to latest shutdown Open for LSMs to hook into from the kernel side Activation is identical to activation of other services Userspace is much simpler, no XML, . . . Priority queues, . . . Race-free exit-on-idle for bus activated services . . . D-Bus in the Kernel

  9. Overview D-Bus in the Kernel

  10. Overview Receiver buffers D-Bus in the Kernel

  11. Overview Receiver buffers Single copy to destination(s) D-Bus in the Kernel

  12. Overview Receiver buffers Single copy to destination(s) Method call windows D-Bus in the Kernel

  13. Overview Receiver buffers Single copy to destination(s) Method call windows Name registry D-Bus in the Kernel

  14. memfds D-Bus in the Kernel

  15. memfds File descriptors for memory regions D-Bus in the Kernel

  16. memfds File descriptors for memory regions Zero Copy! D-Bus in the Kernel

  17. memfds File descriptors for memory regions Zero Copy! Sealing D-Bus in the Kernel

  18. memfds File descriptors for memory regions Zero Copy! Sealing At 512K zero copy is faster than single copy D-Bus in the Kernel

  19. memfds File descriptors for memory regions Zero Copy! Sealing At 512K zero copy is faster than single copy (a bit like Android ashmem) D-Bus in the Kernel

  20. Signal Broadcasting D-Bus in the Kernel

  21. Signal Broadcasting Bloom Filters D-Bus in the Kernel

  22. Signal Broadcasting Bloom Filters Every broadcast message includes bloom filter (calculated by sender) that contains all supported matches, kernel will then simply check receiver bloom filter mask (calculated by receiver) against it. D-Bus in the Kernel

  23. Signal Broadcasting Bloom Filters Every broadcast message includes bloom filter (calculated by sender) that contains all supported matches, kernel will then simply check receiver bloom filter mask (calculated by receiver) against it. Bloom filter uses SipHash, but kernel doesn’t care D-Bus in the Kernel

  24. Policy: D-Bus in the Kernel

  25. Policy: No XML, only simple ACL policy attached to service names D-Bus in the Kernel

  26. Policy: No XML, only simple ACL policy attached to service names More fine-grained access control needs to be done in userspace, but it’s much easier D-Bus in the Kernel

  27. Policy: No XML, only simple ACL policy attached to service names More fine-grained access control needs to be done in userspace, but it’s much easier Use capability checks! D-Bus in the Kernel

  28. Policy: No XML, only simple ACL policy attached to service names More fine-grained access control needs to be done in userspace, but it’s much easier Use capability checks! PolicyKit D-Bus in the Kernel

  29. Differences in Userspace: D-Bus in the Kernel

  30. Differences in Userspace: GVariant used for marshalling (O(1) random access to struct and array fields) D-Bus in the Kernel

  31. Differences in Userspace: GVariant used for marshalling (O(1) random access to struct and array fields) Setup, activation, policy management, driver, proxy lives in systemd D-Bus in the Kernel

  32. Differences in Userspace: GVariant used for marshalling (O(1) random access to struct and array fields) Setup, activation, policy management, driver, proxy lives in systemd New libsystemd-bus client library: waaaaay nicer to use – but not portable to non-Linux D-Bus in the Kernel

  33. Proxy: provides compatibility with dbus1 sockets D-Bus in the Kernel

  34. Proxy: provides compatibility with dbus1 sockets Synthesizes obsolete AcquiredName, LostName, Hello messages D-Bus in the Kernel

  35. Proxy: provides compatibility with dbus1 sockets Synthesizes obsolete AcquiredName, LostName, Hello messages Implements XML policy D-Bus in the Kernel

  36. Proxy: provides compatibility with dbus1 sockets Synthesizes obsolete AcquiredName, LostName, Hello messages Implements XML policy Activated on demand, exits on idle D-Bus in the Kernel

  37. Proxy: provides compatibility with dbus1 sockets Synthesizes obsolete AcquiredName, LostName, Hello messages Implements XML policy Activated on demand, exits on idle Remarshals gvariant/dbus1 D-Bus in the Kernel

  38. Driver: translates driver method calls into ioctl calls D-Bus in the Kernel

  39. Driver: translates driver method calls into ioctl calls org.freedesktop.DBus pseudo-service is a real service on kdbus D-Bus in the Kernel

  40. Driver: translates driver method calls into ioctl calls org.freedesktop.DBus pseudo-service is a real service on kdbus Note that driver signals are synthesized on client side, so the driver only handles method calls D-Bus in the Kernel

  41. Driver: translates driver method calls into ioctl calls org.freedesktop.DBus pseudo-service is a real service on kdbus Note that driver signals are synthesized on client side, so the driver only handles method calls Activated on demand, exits on idle D-Bus in the Kernel

  42. Activation: new .busname unit type in systemd D-Bus in the Kernel

  43. Activation: new .busname unit type in systemd Identical to .socket unit types for socket activation D-Bus in the Kernel

  44. Activation: new .busname unit type in systemd Identical to .socket unit types for socket activation dbus1 bus activation files still supported, but only for clients connecting via the proxy D-Bus in the Kernel

  45. libsystemd-bus D-Bus in the Kernel

  46. libsystemd-bus New client library, designed to be easy to use D-Bus in the Kernel

  47. libsystemd-bus New client library, designed to be easy to use Not portable to non-Linux D-Bus in the Kernel

  48. libsystemd-bus New client library, designed to be easy to use Not portable to non-Linux Assemble and parse messages with format strings D-Bus in the Kernel

  49. libsystemd-bus New client library, designed to be easy to use Not portable to non-Linux Assemble and parse messages with format strings Handles introspection, signal dispatching, method vtables, properties, object manager D-Bus in the Kernel

  50. libsystemd-bus New client library, designed to be easy to use Not portable to non-Linux Assemble and parse messages with format strings Handles introspection, signal dispatching, method vtables, properties, object manager Lots of convenience functions D-Bus in the Kernel

  51. libsystemd-bus New client library, designed to be easy to use Not portable to non-Linux Assemble and parse messages with format strings Handles introspection, signal dispatching, method vtables, properties, object manager Lots of convenience functions Focus on converting errno from/to bus errors D-Bus in the Kernel

  52. libsystemd-bus New client library, designed to be easy to use Not portable to non-Linux Assemble and parse messages with format strings Handles introspection, signal dispatching, method vtables, properties, object manager Lots of convenience functions Focus on converting errno from/to bus errors Connect to container, connect to remote D-Bus in the Kernel

  53. libsystemd-bus New client library, designed to be easy to use Not portable to non-Linux Assemble and parse messages with format strings Handles introspection, signal dispatching, method vtables, properties, object manager Lots of convenience functions Focus on converting errno from/to bus errors Connect to container, connect to remote Credentials include units, slices, sessions, . . . D-Bus in the Kernel

  54. libsystemd-bus New client library, designed to be easy to use Not portable to non-Linux Assemble and parse messages with format strings Handles introspection, signal dispatching, method vtables, properties, object manager Lots of convenience functions Focus on converting errno from/to bus errors Connect to container, connect to remote Credentials include units, slices, sessions, . . . It’s probably what you want to use when you hack on system level software, and up D-Bus in the Kernel

  55. Android binder D-Bus in the Kernel

  56. Android binder Some similar technical concepts, different semantics D-Bus in the Kernel

  57. Android binder Some similar technical concepts, different semantics No name registry, no broadcasts, no ordering D-Bus in the Kernel

  58. When? D-Bus in the Kernel

Download Presentation
Download Policy: The content available on the website is offered to you 'AS IS' for your personal information and use only. It cannot be commercialized, licensed, or distributed on other websites without prior consent from the author. To download a presentation, simply click this link. If you encounter any difficulties during the download process, it's possible that the publisher has removed the file from their server.

Recommend

Tight Kernel Query Complexity of Kernel Ridge Regression and Kernel -means Clustering Manuel

Tight Kernel Query Complexity of Kernel Ridge Regression and Kernel -means Clustering Manuel

Tight Kernel Query Complexity of Kernel Ridge Regression and Kernel -means Clustering Manuel Fernndez V, David P. Woodruff, Taisuke Yasuda Kernel Method Many machine learning tasks can be expressed as a function of the inner product

389 views • 22 slides
1 Kernel methods & optimization One example of a kernel that is frequently used in practice

1 Kernel methods & optimization One example of a kernel that is frequently used in practice

Machine Learning Class Notes 9-25-12 Prof. David Sontag 1 Kernel methods & optimization One example of a kernel that is frequently used in practice and which allows for highly non-linear discriminant functions is the Gaussian kernel,

240 views • 5 slides
Tight Kernel Query Complexity of Kernel Ridge Regression and Kernel -means Clustering Manuel

Tight Kernel Query Complexity of Kernel Ridge Regression and Kernel -means Clustering Manuel

Tight Kernel Query Complexity of Kernel Ridge Regression and Kernel -means Clustering Manuel Fernndez V, David P. Woodruff, Taisuke Yasuda Overview Preliminaries Kernel ridge regression Kernel -means clustering

476 views • 25 slides
Debugging the Linux Kernel with GDB Kieran Bingham Debugging the Linux Kernel with GDB Many

Debugging the Linux Kernel with GDB Kieran Bingham Debugging the Linux Kernel with GDB Many

Debugging the Linux Kernel with GDB Kieran Bingham Debugging the Linux Kernel with GDB Many of us need to debug the Linux kernel Proprietary tools like Trace32 and DS-5 are $$$ Open source debuggers like GDB lack kernel

884 views • 40 slides
Linux Kernel Synchronization System Calls Synchronization in Kernel the kernel RCU File

Linux Kernel Synchronization System Calls Synchronization in Kernel the kernel RCU File

3/1/20 COMP 790: OS Implementation COMP 790: OS Implementation Logical Diagram Binary Memory Threads Formats Allocators User Todays Lecture Linux Kernel Synchronization System Calls Synchronization in Kernel the kernel RCU File

647 views • 8 slides
D-Bus in the Kernel LinuxCon 2014, Tokyo, Japan May 2014 D-Bus in the Kernel Who? Greg

D-Bus in the Kernel LinuxCon 2014, Tokyo, Japan May 2014 D-Bus in the Kernel Who? Greg

D-Bus in the Kernel LinuxCon 2014, Tokyo, Japan May 2014 D-Bus in the Kernel Who? Greg Kroah-Hartman, David Herrmann, Daniel Mack, Lennart Poettering, Kay Sievers with help from Tejun Heo D-Bus in the Kernel Most newer OS designs started

1.35k views • 111 slides
Linux Kernel Debugging Your kernel just oopsed - What do you do, hotshot? Muli Ben-Yehuda

Linux Kernel Debugging Your kernel just oopsed - What do you do, hotshot? Muli Ben-Yehuda

Linux Kernel Debugging Your kernel just oopsed - What do you do, hotshot? Muli Ben-Yehuda mulix@mulix.org IBM Haifa Research Lab Kernel Debugging, Haifux 2003 p.1/19 Kernel Debugging - Why? Why would we want to debug the kernel? after

308 views • 19 slides
1 Theres a kernel security researcher named Dan Rosenberg whose done a lot of linux kernel

1 Theres a kernel security researcher named Dan Rosenberg whose done a lot of linux kernel

1 Theres a kernel security researcher named Dan Rosenberg whose done a lot of linux kernel vulnerability research Thats unavoidable, but the linux kernel developers dont do very much to make the situation any better. -- Basically, the

625 views • 36 slides
Kernel PCA for SNe Kernel PCA for SNe photometric classification photometric classification

Kernel PCA for SNe Kernel PCA for SNe photometric classification photometric classification

Kernel PCA for SNe Kernel PCA for SNe photometric classification photometric classification Emille E. O. Ishida IAG University of Sao Paulo, Brazil In collaboration with Rafael S. De Souza (KASI) astro-ph/1201.6676 IAU General Assembly,

155 views • 14 slides
The Kernel (and Process) Abstraction Chapter 2-3 OSPP Part I Announcements Today: kernel

The Kernel (and Process) Abstraction Chapter 2-3 OSPP Part I Announcements Today: kernel

The Kernel (and Process) Abstraction Chapter 2-3 OSPP Part I Announcements Today: kernel Asynchrony Processes Protection Kernel The software component that controls the hardware directly and implements the core privileged OS

934 views • 62 slides
Skoltech Skolkovo Institute of Science and Technology Kernel Methods Refresher Kernel trick:

Skoltech Skolkovo Institute of Science and Technology Kernel Methods Refresher Kernel trick:

Quadrature-based Features for Kernel Approximation Marina Munkhoeva , Yermek Kapushev, Evgeny Burnaev, Ivan Oseledets Skoltech Skolkovo Institute of Science and Technology Kernel Methods Refresher Kernel trick: compute

1.01k views • 17 slides
TOS Arno Puder 1 Demo Kernel /* tos/kernel/main.c */ #include <kernel.h> WINDOW

TOS Arno Puder 1 Demo Kernel /* tos/kernel/main.c */ #include <kernel.h> WINDOW

TOS Arno Puder 1 Demo Kernel /* tos/kernel/main.c */ #include <kernel.h> WINDOW window_top = {0, 0, 80, 12, 0, 0, ' '}; WINDOW window_bottom = {0, 12, 80, 13, 0, 0, ' '}; void kernel_main() { for (int x = 0; x < 80 * 25 * 2; x++)

830 views • 7 slides
Introduction to Linux Kernel Modules Luca Abeni luca.abeni@santannapisa.it Linux Kernel Modules

Introduction to Linux Kernel Modules Luca Abeni luca.abeni@santannapisa.it Linux Kernel Modules

Introduction to Linux Kernel Modules Luca Abeni luca.abeni@santannapisa.it Linux Kernel Modules Kernel module: code that can be dynamically loaded/unloaded into the kernel at runtime Change the kernel code without needing to reboot

545 views • 13 slides
1 CPU Events: Interrupts and Exceptions CPU Events: Interrupts and Exceptions Protecting Entry

1 CPU Events: Interrupts and Exceptions CPU Events: Interrupts and Exceptions Protecting Entry

Processes and the Kernel Processes and the Kernel The kernel sets processes up process in private data data execution Processes, Protection and the Kernel: Processes, Protection and the Kernel: virtual contexts to address

540 views • 9 slides
A kernel in a library Genodes custom kernel approach Martin Stein <

A kernel in a library Genodes custom kernel approach Martin Stein <

A kernel in a library Genodes custom kernel approach Martin Stein < martin.stein@genode-labs.com > Outline 1. Motivation 2. Overview 3. Scheduling 4. Capabilities 5. Communication A kernel in a library Genodes custom kernel

798 views • 45 slides
Optimization for Kernel Methods S. Sathiya Keerthi Yahoo! Research, Burbank, CA, USA Kernel

Optimization for Kernel Methods S. Sathiya Keerthi Yahoo! Research, Burbank, CA, USA Kernel

Optimization for Kernel Methods S. Sathiya Keerthi Yahoo! Research, Burbank, CA, USA Kernel methods: Support Vector Machines (SVMs) Kernel Logistic Regression (KLR) Aim: To introduce a variety of optimization problems that arise in the

738 views • 59 slides
RESTful WebServices Florian Motlik Webservices now RPC Style SOAP is complicated HTTP not

RESTful WebServices Florian Motlik Webservices now RPC Style SOAP is complicated HTTP not

RESTful WebServices Florian Motlik Webservices now RPC Style SOAP is complicated HTTP not fully used (only post) HTTP Tools not usable (proxy, cache, Firewall) Another layer needed for inspection of SOAP Great for Starting Action on Server

210 views • 9 slides
Trying Your Juvenile Court Case for Appeal and Beyond. Louis P. Milot, Esq. Attorney at Law

Trying Your Juvenile Court Case for Appeal and Beyond. Louis P. Milot, Esq. Attorney at Law

Trying Your Juvenile Court Case for Appeal and Beyond. Louis P. Milot, Esq. Attorney at Law Prosecuting Your Case Use Tools Available under Code of Civil Procedure Venue Substitution Bill of Particulars Motions to

326 views • 8 slides
Session 2: Mapping Ongoing Evidence Generation Joseph F. Naimoli, OHS/USAID Nicole Bonoff,

Session 2: Mapping Ongoing Evidence Generation Joseph F. Naimoli, OHS/USAID Nicole Bonoff,

Generating Evidence of Governance Contributions to Health Outcomes HFG Workshop July 23, 2014 Abt Associates Inc. In collaboration with: Broad Branch Associates | Development Alternatives Inc. (DAI) | Futures Institute | Johns Hopkins

155 views • 13 slides
Applying Geometric Thick Paths to Compute the Number of Additional Train Paths in a Railway

Applying Geometric Thick Paths to Compute the Number of Additional Train Paths in a Railway

Applying Geometric Thick Paths to Compute the Number of Additional Train Paths in a Railway Timetable Anders Peterson Valentin Polishchuk Christiane Schmidt Introduction Routing a Maximum Number of Thick Paths through a

1.44k views • 143 slides
Galder Zamarreo Infinispan Core Developer JBoss by Red Hat Who am I? Core developer for

Galder Zamarreo Infinispan Core Developer JBoss by Red Hat Who am I? Core developer for

Galder Zamarreo Infinispan Core Developer JBoss by Red Hat Who am I? Core developer for Infinispan and JBoss Cache Contributor and committer on JBoss AS, JGroups, Hibernate, JBoss Portal, etc. Agenda What is Infinispan?

272 views • 15 slides
JAXB: Binding between XML Schema and Java Classes Asst. Prof. Dr. Kanda Runapongsa

JAXB: Binding between XML Schema and Java Classes Asst. Prof. Dr. Kanda Runapongsa

JAXB: Binding between XML Schema and Java JAXB: Binding between XML Schema and Java Classes Asst. Prof. Dr. Kanda Runapongsa (krunapon@kku.ac.th) Department of Computer Engineering Khon Kaen University Agenda JAXB Architecture

545 views • 11 slides
Mars Image-based Modeling and Rendering Mars Rovers have 3 cameras Panoramic Camera

Mars Image-based Modeling and Rendering Mars Rovers have 3 cameras Panoramic Camera

Mars Image-based Modeling and Rendering Mars Rovers have 3 cameras Panoramic Camera Hazard Identification Camera Navigation Camera Testing the roll-off on the ground at the JPL Mars Yard sandbox. 1 Panorama Camera

471 views • 8 slides
Welcome to Class 13: Which learning objecHve seems the

Welcome to Class 13: Which learning objecHve seems the

Welcome to Class 13: Which learning objecHve seems the most Was (Is?) Life on Mars? challenging? 1. Instability of liquid H 2 O on Why couldnt

408 views • 5 slides

More recommend