2020-08-20 Project Stratos Sync Meeting notes


  • Anmar
  • Bill Fletcher
  • John Niven
  • Mahtieu Poirier
  • Stefano Stabellini
  • Tom Gall
  • Joakim Beck
  • Randy Linnell
  • Sumit Semwal
  • Diana Craciun
  • Azzedine Touzsni


  • Get a view of the  engineering support avalable to work on Stratos

Discussion items

  • Stefano’s email on Aug 11th to the stratos-dev ML

1) corresponds to STR-10. In the short term it means adding system device tree support for static hypervisors with a reference implementation in Xen. It involves adding support for virtual machines to the system device tree specification, and implement the specification in Xen. 

2) corresponds to STR-11. The current wording is a bit confusing. We haven't settled on whether it should be based on Zephyr or based on Rust. I don't have a strong opinion either way but I have a preference for Zephyr. In any case,

2) is about having a non-Linux dom0 environment that can boot on the Cortex-As or out-of-cluster on the Cortex-Rs/Ms (tomonitor VMs running on the Cortex-As.)

3) is about addressing some of virtio's limitations particularly evident with type-1 hypervisors. In the short term it means getting Virtio to run well with a type-1, Xen being the reference. In particular, this deliverable is expected to enable virtio backends to run well in an unprivileged virtual machine environment. (Today, the virtio backends have to run in an environment with privileges over the entire system.)

Azzedine agrees with Stefano’s approach.

  • Joakim: How does the dev environment look like
  • Stefano: Qualcomm has pre-shared memory patches to be able to use that. Patches were sent to the LKML.  
  • Azzedine: There is a small demo to explain this work. This work can be presented again.
  • There are areas of consideration in performance sensitive situations (attaching an accelerator)
  • Azzedine: From HW point of view, two platforms will be needed
    • MacchiatoBin is used for the AGL testing. Can serve as one of the boards
    • Qualcomm is trying to fill in the gap of the second board (RB5 perhaps)
    • Xilinx board is a possibility
    • From Android perspective: the NXP LX2K board is a very interesting and Pine64Pro board
  • Azzedine: There is a list of items we need to put names next to. The three topics raised by Stefano are a good starting point.
  • FF: AGL is wondering should they virtualize all devices or live with a short list (FM radio is an example)
    • Azzedine: Agrees. We will need a description on such a document/reference/doc then share it widely. Will require feedback from attendees on the call to make sure there is a common agreement
    • Fundamental question: do we allow non-virtualized interfaces
    • Azzedine:  yes
    • FF: it’s worth while to state, on project Stratos, what we are seeking to virtualize and abstract so other orgs (eg. Genivi, AGL) can align.
  • Timeline. PoR needs to be done no later that Sep 15th. Target beta for Sep 3rd (next call)
  • Add other people to this call:
    • There is a group that does automotive (Stefano knows them). They are working on Xen and virtio so very relevant (Epan)
    • Google is another potential candidate
    • OpenSynergy should be invited as well

Action items