Emulate an actual MTD device in Qemu

Having worked with Linux for the last 20 years, and embedded for more than ten of them, I’ve become quite a fan of virtualization in general and Qemu in particular.

Qemu is a fantastic little tool, created by the Open Source superhero Fabrice Bellard. It can be used to verify an embedded system without having to deal with the problems of actual HW until you really have to. Don’t get me wrong, HW excites me like any other nerd, but if the HW is new and shaky it can be quite a pain to develop higher level functions.

My holy grail is to have a 100% complete and accurate virtualization target per architecture to test my various software projects on. That’s why I created TroglOS.

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A life without sudo

Ever since my first stumbling steps with Linux back in ‘96, I’ve been learning about UNIX. The first obvious lesson was to not use the root account. Since then I’ve been using a combination of sudo command and suid root binaries to get the job done. For the last ten years, however, I’ve been meaning to learn about Linux capabilities(7) and thanks to a colleague of mine I now have :) [Read More]

The General Idea

OK, so here’s the general idea: take one teaspoon of a well equipped SBC with Marvell chips you know well, add an awesome WiFi hotspot with USB connection, stir feverishly for several weekends in a row, then sprinkle some AlpineLinux and a custom kernel on top. Enjoy! I have no clue if this will actually work, may even try porting my own little thing called TroglOS to the ClearFog first, I don’t know, but it will definitely be awesome! [Read More]

Fake RAID Adventures

The other day I got my geeky hands on two old SuperMicro X8STI-F 1U servers. I plan to use them as build and embedded target emulation servers for my open source projects as well as Minecraft server for my kids :)

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Upgrade X1 Carbon BIOS from Linux

This is a very brief writeup of how to upgrade the BIOS on a X1 Carbon (G1) from Linux. For more information on this topic there is always the excellent ThinkWiki.

OK, this post is more about creating the bootable USB stick needed, was too much of a chicken to try Flashrom

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Net Install CentOS

I usually run Debian or Ubuntu on my machines. However, having recently found some time to work on my various projects again, I’ve now suddenly found myself in need of a CentOS machine. The CentOS home page invited me to download an installation ISO, so I went for the small Net Install which started perfectly with my virt-manager in Ubuntu. All I had to provide was an FTP server and directory: [Read More]

File System Pass-Through in KVM/Qemu/libvirt

This post doesn’t cover fully setting up KVM/Qemu with virt-manager and creating virtual machine guests. See the Ubuntu KVM Installtion, VirtManager Guide, the Ubuntu Server Guide on libvirt, or HowtoForge for that.

Instead this blog post details the most relevant steps to get file system pass-through between a Linux host and Qemu guest working. The upstream Qemu docs provide a good starting point, as is the original IBM paper on VirtFS. For users of Ubuntu <= 13.04, watch out for the libvirt bug that I know many people run into, myself included.

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