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Latest LWN Articles About Linux (Paywall Has Just Expired)

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Linux
  • SPDX identifiers in the kernel

    Observers of the kernel's commit stream or mailing lists will have seen a certain amount of traffic referring to the addition of SPDX license identifiers to kernel source files. For many, this may be their first encounter with SPDX. But the SPDX effort has been going on for some years; this article describes SPDX, along with why and how the kernel community intends to use it.

    On its face, compliance with licenses like the GPL seems like a straightforward task. But it quickly becomes complicated for a company that is shipping a wide range of software, in various versions, in a whole set of different products. Compliance problems often come about not because a given company wants to flout a license, but instead because that company has lost track of which licenses it needs to comply with and for which versions of which software. SPDX has its roots in an effort that began in 2009 to help companies get a handle on what their compliance obligations actually are.

    It can be surprisingly hard to determine which licenses apply to a given repository full of software. The kernel's COPYING file states that it can be distributed under the terms of version 2 of the GNU General Public License. But many of the source files within the kernel tell a different story; some are BSD licensed, and many are dual-licensed. Some carry an exception to make it clear that user-space programs are not a derived product of the kernel. Occasionally, files with GPL-incompatible licenses have been found (and fixed).

  • 4.15 Merge window part 1

    When he released 4.14, Linus Torvalds warned that the 4.15 merge window might be shorter than usual due to the US Thanksgiving holiday. Subsystem maintainers would appear to have heard him; as of this writing, over 8,800 non-merge changesets have been pulled into the mainline since the opening of the 4.15 merge window. Read on for a summary of the most interesting changes found in that first set of patches.

  • 4.15 Merge window part 2

    Despite the warnings that the 4.15 merge window could be either longer or shorter than usual, the 4.15-rc1 prepatch came out right on schedule on November 26. Anybody who was expecting a quiet development cycle this time around is in for a surprise, though; 12,599 non-merge changesets were pulled into the mainline during the 4.15 merge window, 1,000 more than were seen in the 4.14 merge window. The first 8,800 of those changes were covered in this summary; what follows is a look at what came after.

  • BPF-based error injection for the kernel

    Diligent developers do their best to anticipate things that can go wrong and write appropriate error-handling code. Unfortunately, error-handling code is especially hard to test and, as a result, often goes untested; the code meant to deal with errors, in other words, is likely to contain errors itself. One way of finding those bugs is to inject errors into a running system and watching how it responds; the kernel may soon have a new mechanism for doing this sort of injection.

    As an example of error handling in the kernel, consider memory allocations. There are few tasks that can be performed in kernel space without allocating memory to work with. Memory allocation operations can fail (in theory, at least), so any code that contains a call to a function like kmalloc() must check the returned pointer and do the right thing if the requested memory was not actually allocated. But kmalloc() almost never fails in a running kernel, so testing the failure-handling paths is hard. It is probably fair to say that a large percentage of allocation-failure paths in the kernel have never been executed; some of those are certainly wrong.

  • Tools for porting drivers

    Out-of-tree drivers are a maintenance headache, since customers may want to use them in newer kernels. But even those drivers that get merged into the mainline may need to be backported at times. Coccinelle developer Julia Lawall introduced the audience at Open Source Summit Europe to some new tools that can help make both forward-porting and backporting drivers easier.

    She opened her talk by noting that she was presenting step one in her plans, she hoped to be able to report on step two next year some time. The problem she is trying to address is that the Linux kernel keeps moving on. A vendor might create a driver for the 4.4 kernel but, over the next six months, the kernel will have moved ahead by another two versions. There are lots of changes with each new kernel, including API changes that require driver changes to keep up.

    That means that vendors need to continually do maintenance on their drivers unless they get them upstream, where they will get forward-ported by the community. But the reverse problem is there as well: once a device becomes popular, customers may start asking for it to run with older kernels too. That means backporting.

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Dilution and Misuse of the "Linux" Brand

Samsung, Red Hat to Work on Linux Drivers for Future Tech

The metaverse is expected to uproot system design as we know it, and Samsung is one of many hardware vendors re-imagining data center infrastructure in preparation for a parallel 3D world. Samsung is working on new memory technologies that provide faster bandwidth inside hardware for data to travel between CPUs, storage and other computing resources. The company also announced it was partnering with Red Hat to ensure these technologies have Linux compatibility. Read more

today's howtos

  • How to install go1.19beta on Ubuntu 22.04 – NextGenTips

    In this tutorial, we are going to explore how to install go on Ubuntu 22.04 Golang is an open-source programming language that is easy to learn and use. It is built-in concurrency and has a robust standard library. It is reliable, builds fast, and efficient software that scales fast. Its concurrency mechanisms make it easy to write programs that get the most out of multicore and networked machines, while its novel-type systems enable flexible and modular program constructions. Go compiles quickly to machine code and has the convenience of garbage collection and the power of run-time reflection. In this guide, we are going to learn how to install golang 1.19beta on Ubuntu 22.04. Go 1.19beta1 is not yet released. There is so much work in progress with all the documentation.

  • molecule test: failed to connect to bus in systemd container - openQA bites

    Ansible Molecule is a project to help you test your ansible roles. I’m using molecule for automatically testing the ansible roles of geekoops.

  • How To Install MongoDB on AlmaLinux 9 - idroot

    In this tutorial, we will show you how to install MongoDB on AlmaLinux 9. For those of you who didn’t know, MongoDB is a high-performance, highly scalable document-oriented NoSQL database. Unlike in SQL databases where data is stored in rows and columns inside tables, in MongoDB, data is structured in JSON-like format inside records which are referred to as documents. The open-source attribute of MongoDB as a database software makes it an ideal candidate for almost any database-related project. This article assumes you have at least basic knowledge of Linux, know how to use the shell, and most importantly, you host your site on your own VPS. The installation is quite simple and assumes you are running in the root account, if not you may need to add ‘sudo‘ to the commands to get root privileges. I will show you the step-by-step installation of the MongoDB NoSQL database on AlmaLinux 9. You can follow the same instructions for CentOS and Rocky Linux.

  • An introduction (and how-to) to Plugin Loader for the Steam Deck. - Invidious
  • Self-host a Ghost Blog With Traefik

    Ghost is a very popular open-source content management system. Started as an alternative to WordPress and it went on to become an alternative to Substack by focusing on membership and newsletter. The creators of Ghost offer managed Pro hosting but it may not fit everyone's budget. Alternatively, you can self-host it on your own cloud servers. On Linux handbook, we already have a guide on deploying Ghost with Docker in a reverse proxy setup. Instead of Ngnix reverse proxy, you can also use another software called Traefik with Docker. It is a popular open-source cloud-native application proxy, API Gateway, Edge-router, and more. I use Traefik to secure my websites using an SSL certificate obtained from Let's Encrypt. Once deployed, Traefik can automatically manage your certificates and their renewals. In this tutorial, I'll share the necessary steps for deploying a Ghost blog with Docker and Traefik.