Re: [RFC v2 00/24] Add Realm support to QEMU-VMM

[Kohei Enju <enju.kohei@fujitsu.com>]

On 08/25 15:09, Mathieu Poirier wrote:
> Hi Kohei - apologies for the delayed reply.
> 
> On Thu, Jul 30, 2026 at 02:11:57PM +0900, Kohei Enju wrote:
> > On 07/28 13:26, Mathieu Poirier wrote:
> > > This patchset provides minimal functionality to start a Realm VM
> > > from an Arm RME capable host using the following command line:
> > > 
> > > qemu-system-aarch64 \
> > >  -M confidential-guest-support=rme0 -object rme-guest,id=rme0 \
> > >  -cpu host -M virt -enable-kvm -M gic-version=3,its=on -nodefaults ..
> > > 
> > > It is a refactoring of Jean-Philippe Brucker's initial work dating from a while
> > > back.  It is compatible with Steven Price's v14 revision [1] of his work adding
> > > CCA support to KVM.
> > > 
> > > * We are currently working on rebasing the work to v15.
> > > 
> > > It was tested on the QEMU SBSA machine.  For convenience, a repository is hosted
> > > here [2], along with the TF-A [3], RMM [4] and Linux kernel [5] for the SBSA
> > > machine (compatible with Steven's v14 patchset).
> > > 
> > > Instructions to compile and run the entire stack can be found here [6].
> > > 
> > > Device Assignment is not included.
> > > 
> > > Thanks,
> > > Mathieu
> > 
> > Hi Mathieu, thank you for your work on upstreaming CCA support. I've
> > tested this series in QEMU-TCG(x-rme=on) environments and confirmed
> > that the basic functionality works well.
> > 
> > I have a question about a QMP command for querying CCA capabilities.
> > 
> > Jean's tree contains the following commit adding such a QMP command. Was
> > this functionality intentionally omitted from this series?
> > https://git.codelinaro.org/linaro/dcap/qemu/-/commit/41f7852cc8590a38c47299a35a7238da09ff9a12
> >
> 
> git.codelinaro.org is no longer accessible to me.  Please see if you can point
> me to the same patch in this repository:
> 
> https://gitlab.com/Linaro/cca-public/qemu/-/commits/cca/2025-09-12?ref_type=heads

Hi, thank you for taking a look.

I checked the repository, but could not find the corresponding patch
there. If you agree, I would be happy to share a version of that patch,
updated as needed and rebased onto the latest v3 series.

Thanks,
Kohei

> 
>  
> > We are interested in adding this functionality because we are also
> > planning to upstream CCA support for libvirt, which will need a QMP
> > interface to query the CCA capabilities exposed by QEMU.
> > 
> > Since the Linux kernel dropped some configuration parameters such as the
> > hash algorithm, I need to rework the implementation of that QMP command
> > a bit. If it's okay with you, I'd be happy to send out the reworked
> > patch based on this series.
> > 
> > Thanks,
> > Kohei
> >