Open Source Market Segment LS
Open Source Market Segment RS
Tuesday, 04 February 2014 10:20

SUSE develops module to patch running kernel Featured


Enterprise Linux users could soon have a free means of patching running kernels without any downtime if the efforts of the engineers at SUSE bear fruit.

Developers at the company have come up with what they call kGraft; the technology is in the prototype stage and was developed as a research project, according to a post by Vojtech Pavlik, the director of SUSE Labs and the head of kernel development at SUSE.

Pavlik wrote that while there were a couple of technologies that could be used to patch a running kernel without downtime - Ksplice and OpenVZ Checkpointing - the first would never make it upstream because its open source version was never updated.

Ksplice, which was developed by Ksplice Inc under an open source licence until July 2011 when it was bought by Oracle, is used by the company as an incentive to get companies to use Oracle Linux. Prior to being acquired, it was available for the Red Hat, CentOS, Debian, Ubuntu and Fedora Linux distributions.

Pavlik wrote that  the second solution needed some infrastructure and would not be able to apply a patch without a short interruption of service.

"kGraft builds on technologies and ideas that are already present in the kernel: ftrace and its mcount-based reserved space in function headers, the INT3/IPI-NMI patching also used in jumplabels, and RCU-like update of code that does not require stopping the kernel," Pavlik wrote.  

"A kGraft patch is a kernel module and fully relies on the in-kernel module loader to link the new code with the kernel. Thanks to all that, the design can be nicely minimalistic."

Pavlik wrote that while kGraft was, by choice, limited to replacing whole functions and constants they referenced, this would not limit the set of code patches that could be applied significantly.

"kGraft will offer tools to assist in creating the live patch modules, identifying which functions need to be replaced based on a patch, and creating the patch module source code.," he wrote.

A first kGraft release is planned for next month. The release will be under the GPLv3 licence for parts that touch GCC, and under the GPLv2 licence for Linux kernel parts.

"We aim at getting it merged fully into the upstream projects," he wrote.

Please join our community here and become a VIP.

Subscribe to ITWIRE UPDATE Newsletter here
JOIN our iTWireTV our YouTube Community here


It's all about Webinars.

Marketing budgets are now focused on Webinars combined with Lead Generation.

If you wish to promote a Webinar we recommend at least a 3 to 4 week campaign prior to your event.

The iTWire campaign will include extensive adverts on our News Site and prominent Newsletter promotion and Promotional News & Editorial. Plus a video interview of the key speaker on iTWire TV which will be used in Promotional Posts on the iTWire Home Page.

Now we are coming out of Lockdown iTWire will be focussed to assisting with your webinatrs and campaigns and assassistance via part payments and extended terms, a Webinar Business Booster Pack and other supportive programs. We can also create your adverts and written content plus coordinate your video interview.

We look forward to discussing your campaign goals with you. Please click the button below.



iTWire TV offers a unique value to the Tech Sector by providing a range of video interviews, news, views and reviews, and also provides the opportunity for vendors to promote your company and your marketing messages.

We work with you to develop the message and conduct the interview or product review in a safe and collaborative way. Unlike other Tech YouTube channels, we create a story around your message and post that on the homepage of ITWire, linking to your message.

In addition, your interview post message can be displayed in up to 7 different post displays on our the site to drive traffic and readers to your video content and downloads. This can be a significant Lead Generation opportunity for your business.

We also provide 3 videos in one recording/sitting if you require so that you have a series of videos to promote to your customers. Your sales team can add your emails to sales collateral and to the footer of their sales and marketing emails.

See the latest in Tech News, Views, Interviews, Reviews, Product Promos and Events. Plus funny videos from our readers and customers.


Sam Varghese

Sam Varghese has been writing for iTWire since 2006, a year after the site came into existence. For nearly a decade thereafter, he wrote mostly about free and open source software, based on his own use of this genre of software. Since May 2016, he has been writing across many areas of technology. He has been a journalist for nearly 40 years in India (Indian Express and Deccan Herald), the UAE (Khaleej Times) and Australia (Daily Commercial News (now defunct) and The Age). His personal blog is titled Irregular Expression.

Share News tips for the iTWire Journalists? Your tip will be anonymous




Guest Opinion

Guest Reviews

Guest Research

Guest Research & Case Studies

Channel News