Zack's Kernel News
Zack's Kernel News
Chronicler Zack Brown reports on printk() wrangling, persistent memory as a generalized resource, making Kernel headers available on running systems, and Kernel licensing Hell.
printk() Wrangling
Everyone hates the printk() function, because it's supposed to do something very simple – print output to the console – but in order to do that it has to overcome tremendous obstacles, like producing its output while the system itself is in the very midst of total destruction. Unlike other functions, printk() can't rely on any other part of the system actually working. At least, that's the ideal.
John Ogness recently tried to improve matters. Specifically, among other things, he wanted to free printk() from the constraint of requiring a global lock. He wanted to make it pre-emptible, so that even the deep, dark parts of the kernel that absolutely needed to be able to interrupt everything could still call printk() in times of crisis.
It's a worthy goal. If those deep, dark parts of the kernel can't use printk(), then they can't report what went wrong if they were involved in a system crash. Making printk() pre-emptible would allow every nook and cranny of the kernel to give relevant information that could help to debug the crash.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Kali Linux Waxes Nostalgic with BackTrack Mode
For those who've used Kali Linux since its inception, the changes with the new release are sure to put a smile on your face.
-
Gnome 50 Smooths Out NVIDIA GPU Issues
Gamers rejoice, your favorite pastime just got better with Gnome 50 and NVIDIA GPUs.
-
System76 Retools Thelio Desktop
The new Thelio Mira has landed with improved performance, repairability, and front-facing ports alongside a high-quality tempered glass facade.
-
Some Linux Distros Skirt Age Verification Laws
After California introduced an age verification law recently, open source operating system developers have had to get creative with how they deal with it.
-
UN Creates Open Source Portal
In a quest to strengthen open source collaboration, the United Nations Office of Information and Communications Technology has created a new portal.
-
Latest Linux Kernel RC Contains Changes Galore
Linux kernel 7.0-rc3 includes more changes than have been made in a single release in recent history.
-
Nitrux 6.0 Now Ready to Rock Your World
The latest iteration of the Debian-based distribution includes all kinds of newness.
-
Linux Foundation Reports that Open Source Delivers Better ROI
In a report that may surprise no one in the Linux community, the Linux Foundation found that businesses are finding a 5X return on investment with open source software.
-
Keep Android Open
Google has announced that, soon, anyone looking to develop Android apps will have to first register centrally with Google.
-
Kernel 7.0 Now in Testing
Linus Torvalds has announced the first Release Candidate (RC) for the 7.x kernel is available for those who want to test it.