diff -u: What's New in Kernel Development

Recently there was some discussion about ways to ease the tired backs of kernel maintainers. Apparently the merge windows are times of great labor, and some folks wanted to alert contributors to some preferable code submission habits.

diff -u: What's New in Kernel Development

Nicolas Dichtel and Thierry Herbelot pointed out that the directories in the /proc filesystem used a linked list to identify their files. But, this would be slow when /proc directories started having lots of files, which, for example, might happen when the system needed lots of network sockets.

diff -u: What's New in Kernel Development

David Drysdale wanted to add Capsicum security features to Linux after he noticed that FreeBSD already had Capsicum support. Capsicum defines fine-grained security privileges, not unlike filesystem capabilities. But as David discovered, Capsicum also has some controversy surrounding it.

diff -u: What's New in Kernel Development

Containers are very tricky to implement. Trying to isolate sets of resources from each other completely, so that they resemble a discrete system, and doing it in a secure way, has to be addressed on a feature-by-feature basis, with many caveats and uncertainties.

diff -u: What's New in Kernel Development

Hardware errors are tough to code for. In some cases, they're impossible to code for. A particular brand of hardware error is the Machine-Check Exception (MCE), which means a CPU has a problem. On Windows systems, it's one of the causes of the Blue Screen of Death.

diff -u: What's New in Kernel Development

Kernel configuration has become more and more complex through the years with the proliferation of new drivers, new hardware and specific behaviors that might be needed for particular uses. It has reached about 3,000 config options, and that number will only increase.

diff -u: What's New in Kernel Development

Sometimes a new piece of code turns out to be more useful than its author suspected. Alejandra Morales recently came out with the Cryogenic Project as part of his Master's thesis, supervised by Christian Grothoff. The idea was to reduce energy consumption by scheduling input/output operations in batches.

diff -u: What's New in Kernel Development

Once in a while someone points out a POSIX violation in Linux. Often the answer is to fix the violation, but sometimes Linus Torvalds decides that the POSIX behavior is broken, in which case they keep the Linux behavior, but they might build an additional POSIX compatibility layer, even if that layer is slower and less efficient.

Linux Kernel Testing and Debugging

Linux Kernel Testing Philosophy Testing is an integral and important part of any software development cycle, open or closed, and Linux kernel is no exception to that.

diff -u: What's New in Kernel Development

David Herrmann wanted to disable the virtual terminal subsystem in order to save space on a kernel that didn't need a VT. But, he still wanted to see kernel oops output for debugging purposes. The problem was that only the VT subsystem would display oops output—and he'd just disabled it.

Linux Kernel News - December 2013

Mainline Release (Linus's tree) News The last 3.13 release candidate for 2013 came out on December 29th. This 3.13-rc6 is small with just 81 commits to infiniband, gpu, cpufreq, libata, and block drivers in addition to a few small filesystem fixes, and ARM SoC related changes.

A Handy U-Boot Trick

Embedded developers working on kernels or bare-metal programs often go through several development cycles. Each time the developer modifies the code, the code has to be compiled, the ELF (Executable and Linkable Format)/kernel image has to be copied onto the SD card, and the card then has to be transferred from the PC to the development board and rebooted.

Linux Kernel News - November 2013

Mainline Release (Linus's tree) News 3.13-rc2 has been released on November 29th. This release candidate includes several small bug fixes. Please read the 3.13-rc2 release announcement.

Linux Kernel News - October 2013

Mainline Release (Linus's tree) News Linus Torvalds released 3.12 on November 3 2013 after seven 3.12 rc cycles. This time around, instead of opening the merge window right after the release, Linus chose to delay it by a week. The 3.13 merge window will be open on November 10th. In this release announcement, Linus started a discussion on bug-fix only 4.0 idea.

Bug-Free Linux 4.0?

Well, let’s not get ahead of ourselves here, but Linux founder and “keeper of the flame”, Linus Torvalds, has put developers and the rest of the world on notice that a Linux 4.0 is coming sooner rather than later, “I don't want us to get to the kinds of crazy numbers we had in the 2.x series, so at some point we're going to cut over from 3.x to 4.x, just to keep the numbers small and easy to

September 2013 Linux Kernel News

Mainline Release (Linus's tree) News Linus Torvalds closed the 3.12 merge window when he released 3.12-rc1. tty layer and scalability improvements received a special mention in the release announcement. The tty layer cleanups lead to per-tty locking which will result in better performance on some work-loads.

August 2013 Linux Kernel News

Linus Torvalds released 3.11. Prior to 3.11 release, Linus's 3.11-rc7 announcement was posted to his Google Plus page on Linux's 22nd birthday. Here is what he had to say in his nostalgic and reminiscent statement of the passing of time in which so much has been accomplished. "Hello everybody out there using Linux -

Linux Kernel News - July 2013

The Linux kernel community is busy integrating and testing 3.11 content, working on 3.12 development, and finalizing the topic agenda for the upcoming Linux Conference Europe and Kernel Summit that are scheduled to be held in Edinburgh, UK from October 21-23 2013. Let's start with the release news.