Linux Plumbers Conf 2014

One Line Summary

Abstract

Both kpatch and kGraft use the ftrace facility for their implementation. But the ftrace infrastructure is not yet designed for such a use. The changes needed to be made to ftrace will be discussed. For example, how to handle mixing patching callbacks with tracing callbacks. What to do with multiple users that may want to change the instruction pointer (ip) for the callback function. Should there be a direct jump to a new function that ftrace is aware of instead of calling ftrace itself.

Tags

ftrace, kpatch, kgraft

Speaker

• 

  Steven Rostedt

  Red Hat
  • Website: http://rostedt.homelinux.com/

  Biography

  Steven Rostedt has been working with the Linux kernel since 2001. He currently works for Red Hat working in their Messaging Real-time Grid (MRG) division. He created and maintains Ftrace, the official Linux kernel tracer, and is the current real-time kernel stable maintainer.

  Sessions

  • * Ftrace kernel hooks, more than just tracing
    • Title: Ftrace kernel hooks, more than just tracing
    • Microconference: Refereed Talks
    • Room: Room 2
    • Time: 11:15am
    • One Line Summary:

      The audience is aimed at developers. You do not need to be a kernel developer to enjoy this talk. Just someone that enjoys the art of programming and the crazy ideas that are performed to overcome such obstacles. Live code modification is not trivial, and now the new features of allocating code on the fly makes it even more radical. This is not a trivial task; it requires understanding how the CPU pipeline works as well as all states that the kernel can be in.

    • slides
    • Speakers: Steven Rostedt
  • * Overview of the Live Kernel Patching methods
    • Title: Overview of the Live Kernel Patching methods
    • Microconference: Live Kernel Patching
    • Time: 1:00pm
    • One Line Summary:

      Overview of the three approaches for Live Kernel Patching (kpatch, kGraft and criu+kexec)

    • Speakers: Steven Rostedt
  • * Read Write Semaphore bottlenecks
    • Title: Read Write Semaphore bottlenecks
    • Microconference: Real Time II
    • One Line Summary:

      Handling the difficulties of priority inheritance and Reader Writer semaphores.

    • slides
    • Speakers: Steven Rostedt