Linux Plumbers Conference 2021

Session

Toolchains and Kernel MC

24 Sept 2021, 07:00

Description

The Toolchains and Kernel microconference focuses on topics of interest related to building the Linux kernel. The goal is to get kernel developers and toolchain developers together to discuss outstanding or upcoming issues, feature requests, and further collaboration.

Presentation materials

toolchains-kernel-MC-lpc-2021-notes.txt

12. Toolchains and Kernel MC Welcome

Jose E. Marchesi (GNU Project, Oracle Inc.), Nick Desaulniers (Google)

24/09/2021, 07:00

This is a quick intro to the MC.

The Toolchains and Kernel micro conference focuses on topics of interest related to building the Linux kernel. The goal is to get kernel developers and toolchain developers together to discuss outstanding or upcoming issues, feature requests, and further collaboration.

Suggested Topics:

• Continuous Integration
• Toolchain Feature Requests
• Rust...

78. The Rust toolchain in the kernel

Miguel Ojeda

24/09/2021, 07:05

The Rust for Linux project is adding support for the Rust language to the Linux kernel. If the project is successful, and many drivers start to be written in Rust, then the Rust compiler and associated tools will become a key part of the kernel toolchain.

This raises many questions which we will try to answer and/or discuss with others:

• Which particular Rust toolchain (channels,...

80. objtool on arm64

Josh Poimboeuf (Red Hat), Mark Rutland (Arm Ltd), Peter Zijlstra (Intel OTC), Will Deacon

24/09/2021, 07:35

objtool is heavily used on x86, but isn't currently support upstream by arm64.

In order to avoid depending on objtool to enable any kernel features for arm64 and also to avoid disabling compiler optimisations along the lines of https://git.kernel.org/linus/3193c0836f20 when objtool cannot reconstruct the control flow, how much of its functionality is actually required on arm64 and how much...

81. Report From The Standards Committees

Paul McKenney (Facebook)

24/09/2021, 08:20

Both C and C++ started as strictly single-threaded languages, despite significant multi-threaded use more than 30 years ago. Explicit support for multithreaded execution appeared in 2011, but this was by no means the final word. This presentation will give a quick overview of low-level standards-committee concurrency progress since then, including a snapshot of work on hazard pointers, RCU,...

86. The never-ending saga of control dependencies

Will Deacon, Peter Zijlstra (Intel OTC), Paul McKenney (Facebook), Jade Alglave (Arm)

24/09/2021, 08:50

The Linux kernel continues to rely on control dependencies as a cheap mechanism
to enforce ordering between a prior load and a later store on some of its
hottest code paths. However, optimisations by both the compiler and the CPU
hardware can potentially defeat this ordering and introduce subtle,
undebuggable failures which may only manifest on some systems.

Improving the robustness...

154. Optimizing Linux Kernel with BOLT

Maksim Panchenko (Facebook)

24/09/2021, 09:35

Previous research has demonstrated that the Linux Kernel can benefit greatly from the latest compiler optimization techniques. Binary Optimization and Layout Tool (BOLT) is successfully used to accelerate large applications compiled with PGO and LTO by further improving the code layout to favor underlying hardware page and instruction caching. However, applying BOLT to the kernel faces...

90. Compiler Features for Kernel Security

Kees Cook (Google), Qing Zhao

24/09/2021, 10:05

GCC and Clang both have a variety of security features available, but they are not always at parity with each other. This discussion will review the security features important to the Linux kernel with regard to what's working, what's missing, and what needs adjustment.

Specifically, these areas will be discussed along with anything else that seems relevant:

• stack protector guard...