On Thursday, January 15th, 2026 at 10:51 AM, Jan Beulich <[email protected]>
wrote:
>
>
> On 15.01.2026 00:42, Milky wrote:
>
> > On Wednesday, January 14th, 2026 at 11:12 AM, Jan Beulich [email protected]
> > wrote:
> >
> > > On 14.01.2026 11:58, Milky wrote:
> > >
> > > > Just wanted to update this thread to say that now another T480 user
> > > > (the T480 is a very similar model to my T480S) using the release builds
> > > > of libreboot (as of 26.01 RC1) also has the entries missing from the
> > > > ACPI tables. That discussion was here
> > > > https://codeberg.org/libreboot/lbmk/issues/394. So this confirms that
> > > > I'm running a standard libreboot, rather than a bad build.
> > > >
> > > > Do you think there is any way to avoid the underclocking issue with Xen
> > > > on such devices/firmware?
> > >
> > > In principle there is, but in the absence of ACPI data that means holding
> > > model-
> > > specific data in Xen. Which iirc is what the intel-pstate driver in Linux
> > > does
> > > (using ACPI info nowadays only as "auxiliary" data). But I may be wrong
> > > there,
> > > as it has been a long time since I last looked at that driver.
> >
> > In that case, would you say this is settled now? Would it make sense to
> > report back to the QubesOS community that librebooted T480/S will run
> > underclocked, due to the missing data in ACPI tables and lack of native
> > support in Xen? This information is important, as the device is only barely
> > usable.
>
>
> What to suggest to the Qubes community needs to be discussed there, I think.
>
> Jan
I was just hoping to confirm with you that my understanding is correct, in
order not to pass the wrong information. In fact I intend to report this to the
libreboot/coreboot community too, in case there is a way to include the missing
data in ACPI tables. But first I wanted to make sure that from the Xen
perspective, we got to the bottom of it.
Thanks for your time.
