With the dawn of a new year, Greg Kroah-Hartman has released the 22.214.171.124, 3.0.15 and 3.1.7 kernels. They are intended to resolve resume issues which a lot of people had reported. These versions were followed a few days later by the 126.96.36.199 long-term kernel and the 3.0.16 and 3.1.8 stable kernels.
In a blog posting and in an email to the LKML, Kroah-Hartman also outlined his plans for future maintenance of the various kernel versions. He will stop maintaining the 3.1 series shortly, with just one or two further versions to follow. Following the usual practice for stable kernels, Linux 3.2 will continue to be maintained until shortly after the release of Linux 3.3.
Linux 3.0, which had been designated as a stable kernel, will be promoted to long-term kernel status. Kroah-Hartman will continue to maintain this kernel for at least two years, in accordance with his proposal in discussions on how to manage stable and long-term kernels held a few months ago.
Kroah-Hartman plans to drop support for long-term kernel 2.6.32 shortly, probably in "a month or so". It is possible that someone else will take over at this point, but he does not want to promise anything. Against this background, however, he noted that all other long-term kernels are maintained by other developers and that he is unable to comment on their plans.
In response to Kroah-Hartman's announcement, Steven Rostedt noted that he also plans to maintain the Linux 3.0-based RT kernel (3.0.y-rtx), optimised for real-time use, for two years.
- Developer argp has put together a long blog posting which explains how the kernel’s three memory allocators – SLAB, SLUB and SLOB – work. Modern kernels use one of these to manage and allocate small parcels of memory and they are consequently key factors in determining system performance.
Graphics hardware support
- AMD developer Alex Deucher has revised some of the tables on the Xorg wiki, which are useful when decoding graphics chip and product names of AMD graphics hardware. This information can be used to determine details such as which 7000 series Radeon HD models are based on Northern Islands graphics cores, for which open source Linux drivers have long been available. Other graphics cards in the 7000 series, which was introduced in December, currently require the use of proprietary Linux drivers. According to reports and mailing list posts, AMD developers are working on open source Linux drivers, and these should be released sometime in the next few weeks or months.
- Shortly before the new year was ushered in, Keith Packard released the first release candidate of X Server 1.12. It includes multitouch support, which was discussed in the last regular edition of Kernel Log. The final release of 1.12 is scheduled for March. Peter Hutterer, the driving force behind the multitouch implementation in X Server, explores various aspects of "multitouch in X" in his blog postings Getting Events, Pointer Emulation and Touch Grab Handling.
- The next version of OpenGL implementation and 3D driver collection Mesa 3D is currently in preparation and will bear the version number 8.0. The developers decided to make this a major version number increment because the new version, which is due out in February, will be the first to fully support OpenGL 3.0.
- Daniel Vetter has released version 1.1 of intel-gpu-tools. It contains testing and bug-detection tools primarily aimed at Intel graphics hardware.
- Kernel and X.org developer Dave Airlie has posted details of progress on hotplug servers (an X Server that can use hot swapped graphics hardware without requiring a restart) on his blog. Areas where this may prove useful include USB monitors and systems on which it is possible to switch between processor graphics and a separate graphics chip.
Kernel plumbing layer, userland drivers, developer tools, etc.
- Lucas De Marchi and Gustavo Barbieri have released version 3 of Kmod (1, 2). The new version adds a replacement for depmod, meaning that it now contains everything it needs to supersede module-init-tools (which contains utilities such as lsmod and modprobe). According to both the developer team (1, 2) and the module-init-tools maintainer, firm plans for this succession have now been made.
- Stephen Hemminger has released version 3.2 of iproute2. The new version of the network configuration tools collection, which includes tools such as "ip", is designed to work with Linux 3.2, but also works with older kernel versions.
- Mathieu Desnoyers, the driving force behind tracing solution LTTng, has released LTTng 2.0 prerelease bundle 20111223.
- The recently released version 3.2.3 of software RAID tool mdadm includes better support for reshape on Intel HostRAID controllers. Reshape is used to enlarge existing RAID arrays or migrate existing data to a different RAID level.
- Karsten Keil has released git repositories containing software that enables CAPI 2.0 support on passive ISDN chips which use an mISDN driver. One effect of this is to enable passive ISDN cards to send faxes, a benefit that the developer has successfully tested.
- Tim Bird, one of the driving forces behind the Android mainlining project, has submitted the Android logger to LKML for assessment. His aim is to prepare Android's logging framework for merger. The result was extensive criticism of the patch, which is small at 700 lines, and of the approach used. Bird has recently reawakened the discussion by posing the question of whether, despite all the criticism of the implementation, merging the code might not nonetheless be a good idea.
- Linus Torvalds has once again pointed out that new kernel features should almost never include a configuration option enabling them by default. It is only a few weeks since he reminded various kernel developers that regressions during kernel development are "absolutely unacceptable".
Further background information about the developments in the Linux kernel area can be found using the search function at The H Open Source. Information about previous Linux kernel releases can be found in The H's Linux Kernel History. New editions of Kernel Logs are also mentioned on Identi.ca and Twitter by @kernellog2. The Kernel Log author also posts updates about various topics on Identi.ca and Twitter as @kernellogauthor.