Re: [PATCH v2 0/3] arm64/virt: Add Arm CCA measurement register support

[Jason Gunthorpe <jgg@ziepe.ca>]

On Tue, Sep 29, 2026 at 08:42:36PM +0100, Yeoreum Yun wrote:
> On Tue, Sep 29, 2026 at 04:20:51PM -0300, Jason Gunthorpe wrote:
> > On Tue, Sep 29, 2026 at 05:57:46PM +0100, Yeoreum Yun wrote:
> > > This series adds support for Arm Confidential Compute Architecture (CCA)
> > > measurement registers in the Linux kernel, enabling guest Realms to
> > > access, extend, and expose measurement values for attestation and runtime
> > > integrity tracking.
> > 
> > I'd prefer not to add any more tsm_measurements users until we bottom
> > out on the attestation subsystem.. Mainly because it establishes uAPI
> > that doesn't really do everything people need from this stuff..
> 
> Tend to agree. However, I think this seems like an integration with
> the attestation subsystem.
> IOW, although the functionality and interface are currently scattered,
> the functionality of the TSM MR doesn't change —
> showing the current measurement register status and generating
> a token with a challenge. Therefore, even if the subsystem is refactored,
> I don't think this would be a burden for it, and personally,
> I'd like to see this patch series emancipated from almost six months of waiting ;)

Yeah, but it immediately establishes a sysfs uAPI that we don't want
anyone to implement :( That's my main issue..

Jason