Author Archives: daveti

Unknown's avatar

About daveti

Interested in kernel hacking, compilers, machine learning and guitars.

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

vmrun – run your VMware VM without GUI

Posted on June 5, 2014 by daveti

Virsh is my favorite cmdline for KVM management. You may wonder if there is sth similar for VMware or want to run VMware without GUI. Here is goes – vmrun. 0. VIX API VIX API allows users to automate the … Continue reading →

Posted in Programming | Tagged , , | 8 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

Gumstix Overo – USB gadget mass storage

Posted on April 1, 2014 by daveti

This post introduces the general procedure to make gumstix overo work as an USB gadget mass storage using the Yocto Linux. Thanks Adam Lee (Gumstix) for the gadget configuration consulting and debugging. Thanks Tyler Nichols (OSIRIS Lab) for the hardware … Continue reading →

Posted in Embedded System, Linux Distro, OS | Tagged , , , , , , , | 121 Comments

nested KVM – just for fun

Posted on March 30, 2014 by daveti

KVM is based on virtualization instruction set – either Intel vmx or AMD svm, which provides the ability to run the VM directly without emulation or translation. In other words, KVM could only be enabled if it sees vmx/svm in … Continue reading →

Posted in Linux Distro, Network, OS | Tagged , , , , , , , , , | 2 Comments

top or glances – trust on /proc/meminfo

Posted on March 25, 2014 by daveti

You may notice that the output of top and glances differs on memory usage (if you are using top and glances the same time). This post will disclose some details about memory info collection by glances and top. And the … Continue reading →

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

Hack – make VMware Player 6.0.1 start on Linux kernel 3.13.X

Posted on March 4, 2014 by daveti

If you were using VMware Player 6.0.1 on the latest Linux kernel 3.13.X and not able to get it started. Please read thru this post. 0. Error – failure to build vmnet Inspect the VMware starting log /tmp/vmware-root/modconfig-XXXX.log, we may … Continue reading →

Posted in OS | Tagged , , | 14 Comments

Something about float point math – function call vs. operator

Posted on March 2, 2014 by daveti

This post is triggered by a question of Python – “Is there any difference between pow() and ** operator?”. Similarly, this question applies to C and Java – “Is there any difference between pow(1, 2) and 1*1?”. The first thing … Continue reading →

Posted in Programming, Stuff about Compiler | 1 Comment