Installing without IOMMU but my hardware is supported

Hello, I would like to know if I ignore the famous “Unsupported Hardware Detected” message and go ahead with the install anyway…but then edit the Xen command line after first boot will I be fine?

My motherboard and CPU is in the HCL with IOMMU support, and if I flash Dasharo bios I get the message but with Heads I don’t for example.

I ask because I haven’t figured out how to get the installer to append “iommu=force” but know how once the OS is installed. But just want to make sure I am not forgoing the security features or how to check everything is running as expected now?

In BIOS or UEFI North bridge configuration. Enable virtualisation there too. (And on the CPU of course) Install should work normally without tweaking on supported hardware.

Thanks for the reply, but it didn’t really answer my question.

You can change the configuration after the installation, unless the issue is resolved you are unlikely to be able to start any VMs.

You need to add iommu=force to the GRUB_CMDLINE_XEN part of the grub configuration, you can test if it works by manually editing the parameters on the grub boot screen by hitting the ‘e’ key.

If fare as I know, both Dasharo and Heads rely on Coreboot for the IOMMU support, and it works on my hardware running Dasharo without using iommu=force.

Ah okay, thanks for the info! That helps my understanding…I did find it odd that Dasharo BIOS brought the message whereas Heads did not.

The reason I thought it may be a problem is because after disk decryption some of my USB ports seem to stop working. Like if I plug in a mouse the optical light doesn’t come on and there is no sys-usb pop up. Any thoughts on that?

We will need your hardware specs to even begin diagnosing that issue