about livepatching, working with RISC-V extensions and creating a kernel module for the memory extender
On October 30 at 19:00, engineers from YADRO and the local Linux User group will open a series of joint meetups. They will share their experience of spot updating the Linux kernel using livepatching, talk about support for the RISC-V architecture and extensions, and about the design of the DMA subsystem.
Registerto reserve a place on the site – the number of places is limited. But for those who don’t have time, a broadcast will be available on VK, YouTube or Rutube (also by registration) and a registration sheet for the next Linux meetups will be open.
What's in the program
Livepatching: “pointed” Linux kernel updates without rebooting
Evgeniy Shatokhin
Lead Software Engineer, YADRO
Linux-based server systems often run non-stop for months or even years. But what if serious errors are detected in the kernel, and updating and rebooting the system to fix them is time-consuming and expensive?
Livepatching, a technology for “pointed” updates of the Linux kernel, allows you to do not only without rebooting, but even without stopping running processes for a significant time.
I'll tell you:
How to use livepatching to fix errors that lead to kernel oops or security vulnerabilities.
How you can use dynamic Ftrace to “replace” some of the functions in a running Linux kernel.
What features and limitations does this technology have for x86, PowerPC and RISC-V.
How to competently organize the preparation, testing and release of a livepatch and avoid pitfalls.
And most importantly, why it is not as difficult as it might seem.
RISC-V architecture and its extensions on Linux
Sergei Matyukevich
Lead Software Engineer, Syntacore
RISC-V is developing and gradually gaining popularity. Hardware manufacturers are experimenting with new architecture, releasing new processors and boards. At the same time, support for RISC-V is being developed in the open source ecosystem.
The growing popularity of RISC-V is also due to the ability to create and standardize additional instruction sets, or extensions. Their list grows and changes from processor to processor, so software developers never get bored.
In my speech I will tell you:
What RISC-V extensions are there, which of them are supported by the Linux kernel and why.
How the Linux kernel can learn about available RISC-V extensions on the processor where it is running.
How and why the Linux kernel can share this information with user software.
Expanding the boundaries of available RAM, or Creating your own memory extender module
Dmitry Tochansky
Senior Software Engineer, YADRO
I was faced with the task of connecting a device that only has access to a 32-bit address space with a system in which the RAM is located outside this range.
Using this example, I will show and tell:
How the DMA subsystem works in the Linux kernel and what does iommu have to do with it.
How to implement your own iommu driver without having either a driver or iommu.
Why might you need this?
Where and when do we meet?
October 30, Wednesday. The meetup starts at 19:00, guests gather at 18:30.
In St. Petersburg: Petrocongress center, Chkalovskaya metro station. Entrance by registration — it is needed to secure your place in the hall.
Online: we will send you a link to the broadcast after registration on the website.
