Category Archives: Linux Distro

Ubuntu Kernel Build Again

Posted on November 7, 2019 by daveti

I wrote two blog posts about Linux kernel build on Ubuntu [1,2]. There is also an official wiki page talking about the same thing [3]. Still, things are broken when I try to create a homework assignment for my class. … Continue reading →

Posted in IDE_Make, Linux Distro, OS | Tagged , , , , , , , , , , , , | 1 Comment

Rowhammer Pine64

Posted on April 29, 2018 by daveti

Rowhammer attacks have been well known, and gotten a lot of publications already. However, we notice that most rowhammers happened on x86 architecture due to the easy access to clflush from the user space. ARM architecture (both ARMv7 and ARMv8) … Continue reading →

Posted in Linux Distro, OS, Security | Tagged , , , , , | Leave a comment

“make deb-pkg” broken

Posted on March 15, 2018 by daveti

Last time when I hacked the Linux kernel on Ubuntu, it was 4.4 on LTS 14.04. Time flies. Now I need to hack the kernel 4.13 again on LTS 16.04, and find the kernel build broken. It is fine that … Continue reading →

Posted in Linux Distro | Tagged , , | 1 Comment

Fedora Upgrade from 21 to 24

Posted on July 24, 2016 by daveti

After almost 5 hours of upgrading, my server has been successfully upgraded from Fedora 21 to Fedora 24, which uses the latest stable kernel 4.6. There is a online post demonstrating how to upgrade from Fedora 21 to 23 using … Continue reading →

Posted in Linux Distro | Tagged , , , | 4 Comments

Linux kernel hacking – one relay file for all CPUs

Posted on November 16, 2015 by daveti

I wrote a post about kernel relay 2 years go (https://davejingtian.org/2013/06/29/relay-linux-kernel-relay-filesystem/). However, I have realized that I did not understand relay until recently when I was debugging a relay-related bug. Though I was working on RHEL 2.6.32 kernel, this post … Continue reading →

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

Linux kernel hacking – support SO_PEERCRED for local TCP socket connections

Posted on October 6, 2015 by daveti

In my old post (https://davejingtian.org/2015/02/17/retrieve-pid-from-the-packet-in-unix-domain-socket-a-complete-use-case-for-recvmsgsendmsg/), we talked about how to retrieve the peer PID from Unix domain socket using struct ucred. A more smart way to do this is using getsockopt() syscall with option SO_PEERCRED directly. As you expected (or … Continue reading →

Posted in Linux Distro, Network, OS | Tagged , , , , , , , , , , , , , , , , , | 6 Comments

Linux Kernel DSA and Provenance Release

Posted on August 21, 2015 by daveti

Linux Provenance kernel (2.6.32) and tools for CentOS and RedHat Enterprise Linux https://github.com/daveti/prov-kernel https://github.com/daveti/prov-tools Linux kernel crypto – DSA https://github.com/daveti/kdsa During the development on kernel 2.6.32, we found a bug in mpi-pow.c which failed DSA.  The patch file has been included … Continue reading →

Posted in Linux Distro, OS, Security | Tagged , , , , , , , , | Leave a comment

Fedora 21 Workstation – some post installation issues after fedup from 20

Posted on December 22, 2014 by daveti

Believe or not, Fedora’s release upgrade is always troublesome, partially because of the package management imposed, which is initially designed to ease the update for binaries. After the painful experience from Fedora 19 to 20, I have just gone thru … Continue reading →

Posted in Linux Distro | Tagged , , , , , , , , , | 1 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

EXT4-fs error – use Ubuntu to fix Fedora

Posted on May 31, 2014 by daveti

The most terrible thing a Linux could have may be some errors reported by the file system. It is usually caused by power outages or bad blocks/sectors within the hard drive. Eventually, as a Linux user, you may at least … Continue reading →

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