Tag Archives: kernel

KT – use kernel timers in the Linux kernel

Posted on July 9, 2014 by daveti

Compared to start a timer directly in certain kernel thread which will make the thread sleep for a while, using a kernel timer may be much more desired without stopping the current working thread. This post demonstrates a live example … Continue reading →

Posted in OS | Tagged , , | Leave a comment

USB mass storage on Gumstix – a tricky issue using Yocto Daisy

Posted on July 1, 2014 by daveti

A recent upgrade of Yocto, from Dora to Daisy, broke the things worked before. Actually, CONFIG_USB_MASS_STORAGE, enabled in the defconfig of the Overo, was not passed to the .config during the kernel build. This weird missing config costed me 24-hour … Continue reading →

Posted in Embedded System, Linux Distro | Tagged , , , , , , | 2 Comments

ARP – Linux kernel ARP behavior with multiple NIC

Posted on June 27, 2014 by daveti

This post is the summary based on a recent discussion in the kernelnewbies mail list. Thanks to the collective intelligence, the Linux kernel ARP behavior with multiple NIC is now pretty clear. 0. Original Question “Assume there are two interfaces … Continue reading →

Posted in Network, OS | Tagged , , , , | 8 Comments

crypto – use Linux kernel crypto API

Posted on June 18, 2014 by daveti

Crypto is an important part of the Linux kernel source code. One can tell from the standalone crypto directory under the kernel source tree. Device drivers, file system and security all need crypto. This post does not help understand the … Continue reading →

Posted in OS, Programming, Security | Tagged , , , , , | 3 Comments

create Linux kernel proc entry – some good-to-know tricky stuffs

Posted on October 16, 2013 by daveti

It costs me 2 days to make a kernel module written few years ago back to work again. However, there is nothing fancy within the module except adding a new proc entry under /proc/sys/net/ipv4, which I would never know is … Continue reading →

Posted in OS, Programming | Tagged , , | 1 Comment

Official Ubuntu Linux kernel build (with IMA enabled)

Posted on August 20, 2013 by daveti

As a branch of Debian, Ubuntu shares the same ideas on Linux kernel build, but with some difference. This post takes a great reference to the Ubuntu official wiki page on how to do kernel build. Moreover, we are going … Continue reading →

Posted in OS | Tagged , , , | 3 Comments

nex – Linux netlink programming for kernel and user spaces

Posted on August 19, 2013 by daveti

There are ways to communicate with Linux kernel, including /proc, debugfs, syscall and etc. Most of them are unidirectional, from the kernel to the user space. /proc could be used to ‘write’ to the kernel but mostly in small data … Continue reading →

Posted in Dave's Tools, OS, Programming | Tagged , , | Leave a comment

Build official Debian linux kernel

Posted on August 1, 2013 by daveti

Comparing with ‘normal’ Linux kernel build, the ‘official’ Linux kernel build for each distribution is confusing and awkward. Debian 7.1 Wheezy may be friendly but still needs cautions. The good thing is you do not need to patch the original … Continue reading →

Posted in OS | Tagged , , , , , | 1 Comment

relay – linux kernel relay filesystem

Posted on June 29, 2013 by daveti

Relay (Relay filesystem) is a mechanisim used to transfer the data from the kernel space to the user space within the Linux OS. The advantage of relay comparing with other means like debugfs or proc is its ability to handle … Continue reading →

Posted in OS, Programming | Tagged , , , , | Leave a comment

Add a new syscall into Linux kernel – for fedora 18 with kernel 3.8.7

Posted on April 17, 2013 by daveti

Adding a new syscall into Linux kernel would be tricky for the beginners (like myself), especially considering the kernel source tree structure changes among different versions. It seems most of the online tutorials focusing on older versions of kernel (2.6.X) … Continue reading →

Posted in OS | Tagged , , , , | Leave a comment