OpenSUSE Adds Option To Installer For Toggling Performance-Hitting CPU Mitigations


With the newly released openSUSE Leap 15.1 they have added an option to their installer for toggling the CPU mitigations around Spectre / Meltdown / Foreshadow / Zombieload to make it very convenient should you choose to retain maximum performance while foregoing the security measures. But it also allows disabling SMT/HT from the installer should you prefer maximum security.

When installing openSUSE Leap 15.1 today, I was a bit surprised to see a “CPU mitigations” option that allows toggling the value similar to the mitigations= kernel command line option.

This is the first major Linux distribution installer I’ve seen that makes it so easy and visible to change the CPU mitigations. Though to novice users they could be left wondering what it’s all about or even accidentally turning it off, but we’ll see. Hopefully more Linux distributions educate their users on the performance costs to these mitigations and make it so easy to tune the mitigations.

It’s useful just not for disabling the mitigations but also for setting auto,nosmt given that it’s looking like Hyper Threading is insecure.

In case you missed it, this week I did run fresh benchmarks looking at the mitigated costs for servers, desktops, and a laptop. Additional Zombieload and Meltdown/Spectre/L1TF/MDS tests are forthcoming on Phoronix.