Re: [RFC PATCH v1 2/2] cgroup/misc: Add support for Arm CCA MECIDs

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

On 07/24 14:52, Michal Koutný wrote:
> Hello Kohei.
> 
> On Fri, Jul 24, 2026 at 06:40:56PM +0900, Kohei Enju <enju.kohei@fujitsu.com> wrote:
> > Arm CCA MECIDs are limited platform resources. Add a misc cgroup
> > resource to allow the system administrator to account for and limit
> > their use.
> > 
> > The cca_mec resource represents the number of Realm VMs using the
> > private MEC policy. Each such Realm consumes one MECID. Charge the
> > resource when the Realm is created, and uncharge it when the Realm is
> > successfully destroyed.
> > 
> > Realms using the shared MEC policy don't consume this resource.
> > 
> > Signed-off-by: Kohei Enju <enju.kohei@fujitsu.com>
> > ---
> >  arch/arm64/include/asm/kvm_rmi.h |  2 ++
> >  arch/arm64/kvm/rmi.c             | 44 +++++++++++++++++++++++++++++++-
> >  drivers/firmware/arm_rmm/rmi.c   |  4 +++
> 
> (mainly for this)
> >  include/linux/misc_cgroup.h      |  4 +++
> >  kernel/cgroup/misc.c             |  4 +++
> >  5 files changed, 57 insertions(+), 1 deletion(-)
> 
> Conditional
> Acked-by: Michal Koutný <mkoutny@suse.com>
> (it makes sense along the other arches' miscresurces)

Hi Michal,
Thank you for taking a look.

> 
> Why? I see this [1] (or followup) needs to be added first.

Yes, [1] should be added first.
As also stated in the coverletter, the following series is anothor
dependency, because this RFC series is on top of those other series.
https://lore.kernel.org/all/20260715142841.80544-1-steven.price@arm.com/

The [1] series is a dependency of the one above, and I didn't mention it
explicitly in the cover letter. My bad.

My intention was to get feedback on this RFC series about the
architecture and the basic design until those dependent series are
merged, after which I will send this series as non-RFC.

Thanks,
Kohei

> 
> Thanks,
> Michal
> 
> [1] https://lore.kernel.org/r/20260715142739.80398-4-steven.price@arm.com/