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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.

More in Tux Machines

Today in Techrights

today's leftovers

  • Debian XU4 images updated
    I've updated my Debian images for the ODROID XU4; the newest build was done before stretch release, and a lot of minor adjustments have happened since then.
  • Parrot 4.0 Ethical Hacking Linux Distro Released
  • FBI says Russians hacked [sic] hundreds of thousands of home and office routers

    The warning followed a court order Wednesday that allowed the FBI to seize a website that the hackers [sic] planned to use to give instructions to the routers. Though that cut off malicious communications, it still left the routers infected, and Friday’s warning was aimed at cleaning up those machines.

  • FBI tells router users to reboot now to kill malware infecting 500k devices

    Researchers from Cisco’s Talos security team first disclosed the existence of the malware on Wednesday. The detailed report said the malware infected more than 500,000 devices made by Linksys, Mikrotik, Netgear, QNAP, and TP-Link. Known as VPNFilter, the malware allowed attackers to collect communications, launch attacks on others, and permanently destroy the devices with a single command. The report said the malware was developed by hackers [sic] working for an advanced nation, possibly Russia, and advised users of affected router models to perform a factory reset, or at a minimum to reboot.

Software and Games: KStars, Opera, OpenStack, MariaDB and More

  • KStars 2.9.6 is Released!
    I'm glad to announce the release of KStars 2.9.6 for Windows, MacOS, and Linux. This is a minor bugfix release.
  • Opera 54 Browser Enters Beta with News on the Speed Dial, Update & Recovery Menu
    Opera has promoted its upcoming Opera 54 web browser to the beta channel, giving us a glimpse of what to expect from the final version, due for release sometime next month. Based on the open-source Chromium 67.0.3396.18 web browser, Opera 54 recently entered beta stages of development with a plethora of new features and improvements, among which we can mention a new Update & Recovery Opera menu page that makes it easier for users to update the web browser and reset it to its default state, including the ability to clear temporary data, such as cookies.
  • OpenStack at a Crossroads
    The OpenStack of a few years ago is dead, however. What has emerged from the hype cycle is a materially different foundation, mission and software stack, with a great deal of change still ahead of it.
  • The OpenStack Foundation grows beyond OpenStack
    The OpenStack Foundation has made a considerable change to its development process and governance structure by introducing two open source projects that are not part of the OpenStack cloud platform. This week, the organization launched version 1.0 of Kata Containers - a runtime system with an emphasis on speed and security, enabling users to boot a VM in as little as five seconds - and introduced a brand new project called Zuul, spinning out the software development and integration platform that has been used by the OpenStack community internally since 2012.
  • Oracle nemesis MariaDB tries to lure enterprise folk with TX 3.0
    Open-source database biz MariaDB has upped the ante in its war against Oracle, promising enterprise customers better compatibility with – and easier migration from – Big Red. The Finnish firm's latest offering, MariaDB TX 3.0, released for GA today, extends the number of use cases to include temporal processing and advanced data protection for sensitive and personally identifiable information, as well as Oracle compatibility. The broad aim is to tap into customers' grumbles over legacy vendor lock-in, while convincing the bigger customers that they can move to an open-source database without compromising performance.
  • The Humble Monthly Bundle just added two great Linux games
    For those that are interested, you can secure a copy of two great Linux games in the current Humble Monthly Bundle. Just added today are: Get Cook, Serve, Delicious! 2!! Ken Follett's The Pillars of the Earth
  • SC-Controller 0.4.3 Released, Support Steam Controller & Sony DS4 Over Bluetooth
    For those looking to manage your Steam Controller and other supported Linux gaming peripheral input devices outside of Steam, there is a new release of the independently-developed SC-Controller Linux user-space software. While Linux 4.18 is bringing the Steam Controller kernel driver, for those looking for a Steam Controller solution right now to enjoy this excellent gaming controller for now outside of Steam, SC-Controller fills that void.

Huawei, Fuchsia and More

  • Huawei will no longer allow bootloader unlocking (Update: Explanation from Huawei)

    "In order to deliver the best user experience and prevent users from experiencing possible issues that could arise from ROM flashing, including system failure, stuttering, worsened battery performance, and risk of data being compromised, Huawei will cease providing bootloader unlock codes for devices launched after May 25, 2018. [...]"

  • Fuchsia Friday: How ad targeting might be a hidden cost of Fuchsia’s structure
     

    Fuchsia, by its nature, comes with the potential for a handful of new opportunities for ad targeting. Let’s peer into the dark side of Fuchsia’s innovative features.

  • iPhone Quarter, ZTE Troubles, Facebook Troubles, Nokia Come-back
     

    So the past month or two? The Quarterly results cycle came in. The item often of great interest is the Apple iPhone performance. 52.2 million iPhones shipped and that gives roughly a flat market share compared to the year before, so about 14%-15%. I'll come and do the full math later of the quarterly data. That race is no longer in any way interesting.

    But two Top 10 smartphone brands ARE in the news. One who is facing imminent death and the other who is making a miraculous return-from-dead. So imminent death and current Top 10 brand first. ZTE. The Trump administration has put a massive squeeze on ZTE and the company is in serious trouble of imminent collapse. Then bizarrely, Trump reversed course and felt he needed to protect CHINESE employment (???) and after yet another typical Trump-mess, we now are at a Never-Neverland where Trump's own party Republicans are revolting against their President and well, ZTE may end up a casualty of this mess. We'll keep an eye on it.

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