If you have POWER8 systems that you want to keep alive, what are your options in 2022? You can keep using the legacy distribution you're still using as long as it's still supported, but if you want some modernisation, that might not be the best option for you. Here's the current landscape of POWER8 support in major distributions, and hopefully it helps you out!| sthbrx.github.io
I was staring at some assembly recently, and for not the first time encountered rfid and hrfid, two instructions that we use when doing things like returning to userspace, returning from OPAL to the kernel, or from a host kernel into a guest.| sthbrx.github.io
In OpenPOWER land we have a project called op-test-framework which (for all its strengths and weaknesses) allows us to test firmware on a variety of different hardware platforms and even emulators like Qemu.| sthbrx.github.io
Just recently Petitboot added a method to ask the user for a password before allowing certain actions to proceed. Underneath the covers this is checking against the root password, but the UI "pop-up" asking for the password is relatively generic. Something else which has been on the to-do list for a while is support for mounting encrpyted partitions, but there wasn't a good way to retrieve the password for them - until now!| sthbrx.github.io
Quite often when building small Linux images having separate user accounts isn't always at the top of the list of things to include. Petitboot is no different; the most common operations like mounting disks, configuring interfaces, and calling kexec all require root and Petitboot generally only exists long enough to boot into the next thing, so why not run it all as root?| sthbrx.github.io
On platforms that support it Petitboot can interact with the inband IPMI interface to pull information from the BMC. One particularly useful example of this is the "Get System Boot Options" command which we use to implement boot "overrides". By setting parameter 5 of the command a user can remotely force Petitboot to boot from only one class of device or disable autoboot completely. This is great for automation or debug purposes, but since it can only specify device types like "disk" or "netw...| sthbrx.github.io
Last month, I was in Amsterdam at OpenPOWER Summit Europe. It was great to see so much interest in OpenPOWER, with a particularly strong contingent of researchers sharing how they're exploiting the unique advantages of OpenPOWER platforms, and a number of OpenPOWER hardware partners announcing products.| sthbrx.github.io
A neat piece of kernel code dropped into my lap recently, and as a way of| sthbrx.github.io
This entry is a followup to part I which you should absolutely read| sthbrx.github.io
Userspace| sthbrx.github.io
(Most of the hard work here was done by fellow blogger Rashmica - I just verified her instructions and wrote up this post.)| sthbrx.github.io
NAMD is a molecular dynamics program that can use GPU acceleration to speed up its calculations. Recent OpenPOWER machines like the IBM Power Systems S822LC for High Performance Computing (Minsky) come with a new interconnect for GPUs called NVLink, which offers extremely high bandwidth to a number of very powerful Nvidia Pascal P100 GPUs. So they're ideal machines for this sort of workload.| sthbrx.github.io
Introduction| sthbrx.github.io
POWER8 sounds great, but where the heck can I get a Power VM so I can test my code?| sthbrx.github.io
Here at OzLabs, we have an unfortunate habit of making our shiny Power computers very sad, which is a common problem in systems programming and kernel hacking. When this happens, we like having logs. In particular, we like to have the kernel log and the OPAL firmware log, which are, very surprisingly, rather helpful when debugging kernel and firmware issues.| sthbrx.github.io
This is a tale of a simple problem, with a relatively simple solution, that ended up being pretty complicated.| sthbrx.github.io
So today I saw Freestanding “Hello World” for OpenPower on Hacker News. Sadly Andrei hadn't been able to test it on real hardware, so I set out to get it running on a real OpenPOWER box. Here's what I did.| sthbrx.github.io
(I wrote this blog post a couple of months ago, but it's still quite relevant.)| sthbrx.github.io
I wrote this blog post late last year, it is very relevant for this blog though so I'll repost it here.| sthbrx.github.io