Thomas Huth's blog

This year, we are celebrating the 15th anniversary of QEMU (QEMU 0.1 was announced in March 2003), and to contribute to this celebration, we will have another edition of the QEMU Advent Calendar this year. The new website for the advent calendar is now online at www.qemu-advent-calendar.org – but please...

Note that this is a blog post for (new) QEMU developers. If you are just interested in using QEMU, you can certainly skip this text. Otherwise, in case you have ever been in touch with the QEMU device model (“qdev”), you are likely aware of the basic qdev code boilerplate...

When you are trying to install a s390x Fedora 27 (or RHEL 7.4) KVM guest on an IBM z Systems mainframe by using one of the provided ISO DVD images (e.g. Fedora-Server-dvd-s390x-27-1.6.iso), there are two pitfalls you should be aware of. The first problem is that QEMU’s firmware for the...

When you are trying to start a KVM guest via libvirt on an s390x Linux installation that is running on an older version of z/VM, you might run into the problem that QEMU refuses to start with this error message: cannot set up guest memory 's390.ram': Permission denied. This happens...

Laszlo wrote an article over at the edk2 wiki about testing SMM with OVMF, in QEMU/KVM virtual machines managed by libvirt: https://github.com/tianocore/tianocore.github.io/wiki/Testing-SMM-with-QEMU,-KVM-and-libvirt The primary goal of the article is to help rapid development and testing of SMM-related firmware code (or any edk2 code in general).

Open Firmware has a concept of environment configuration variables that are used to control the boot flow and other behavior of the firmware. On ppc64 systems, these variables are normally stored in the NVRAM of the machine (as defined in the LoPAPR specification, chapter 8.4.1.1, “System NVRAM Partition”), so that...

The QEMU Advent Calendar 2016 website reveals a new disk image for download each day in December until 2016-12-24, to create a fun experience for the QEMU community, and to celebrate the 10th anniversary of KVM. Starting today, on December 1st, the first door of the advent calendar can now...

This year, we are celebrating the 10th anniversary of KVM (see Amit Sha’s article on LWN.net for more information), and the 25th anniversary of Linux, so to contribute to this celebration, Kashyap Chamarthy and I are preparing another edition of the QEMU Advent Calendar this year. The QEMU Advent Calendar...

While it’s also possible to load single files via the Open Firmware interface already (by typing something like “boot net:” at the firmware prompt for example), you need a secondary boot loader like yaboot or GRUB 2 to handle more complex boot scenarios like loading both, kernel and an initrd....