Re: [PATCH 0/3] arm64/virt: Add Arm CCA measurement register support

From: Yeoreum Yun

Date: Tue Sep 29 2026 - 12:06:17 EST


Hi Jason,

> On Wed, Apr 22, 2026 at 08:57:00AM +0000, Sami Mujawar wrote:
>
> > > So this is tying it to the same FW event log that TPM uses.
> > >
> > > I think that strengthens my point this should all be uninform. TPM
> > > drivers are directly exposing the event log today, but I guess that
> > > needs generalization if non-TPM drivers are going to present it as
> > > well.
> > >
> > > How do you imagine getting and manipulating the EFI event log to use
> > > with this?
> >
> > The event logs from UEFI will be handed off to the OS using CCEL
> > ACPI table. The CCEL table spec update can be seen at
> > https://github.com/tianocore/edk2/issues/11384
>
> I ment from linux userspace. event log is well establihsed in the aCPI
> side for TPM and in Linux today it is only exposed to userspace
> through TPM.
>
> This is not TPM, so how do you intend to give the event log to
> userspace?

The event log would be exported via /sys/firmware/acpi/tables/data/CCEL
with binary format just as TPM event log is also exported with binary
format via binary_bios_measurements.

Instead of Sami, I'll post v2 which rebased on for-next/smccc-bus in
arm64 tree.

Thanks.

--
Sincerely,
Yeoreum Yun