Fedora for RISC-Vi, David and Rich (2024)
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Abstract, slides, and video:

    https://pretalx.com/devconf-cz-2024/talk/Q7XB3M/

    https://www.youtube.com/watch?v=qS12_HgbNog

General:

- RISC-V is about 12 years old
- c10s is based on F40
- Fedora:
  - Kiwi-generated images
- Works with QEMU, cloud-init, EDK2
- No bootloader (GRUB2 or 'sdboot'), direct booting the kernels
- Boards with best upstream support?

Landscape:

- RVI (RISC-V international) is the "foundation" that controls the ISA specification.
  - "RVI is to RISC-V instruction set, what Red Hat is to open source software"
  - tech.riscv.org/groups

- RHT is a member via IBM; individuals can also get access to it (but
  you don't have

- RVI technical groups: many of them (73) - hypervisors, toolchains,
  runtime integrity + steering committees and task groups

- "RISE" (RISC-V Software Ecosystem)
  - https://riseproject.dev
  - RHT contributes 2 full-time equivalent to RISE
  - It deals with the software layer, Linux distros
  - They also have technical steering committes (TSC): compilers &
    toolchains, distro integration, kernel & virt
  
- RVI "Profiles" - this is an important concept for us
  - https://lists.riscv.org/g/sig-profiles
  - RISC-V is an "extensible" architectre: so there are many possible
    extensions
  - To construct a UNIX server, or embedded, etc
  - "RVA23": vector extensions, hypervisor, perf counters, cache, etc
    - On x86: AVX, etc provide performance
  - All the specs are available online
  - Waiting for hardware
  - For Fedora, we don't want to exclude people using cheaper (but
    reliable) boards, as they'd be common
  - "RVA24" — we don't know what it'll be called; because they'll be
    dated
  
- For CentOS 10 Stream - the "balance" might be difficult
  - As of 2024 June, there are still some downstream-specific software

- Working on RISC-V on Fedora: 
  - Rich worked a lot for 
  - Fedora Rawhide: 24K RPM packages!
  - CentOS 10 Stream: 2389 software (almost a 10th of Fedora)

- Koji
  - RISC-V rocks
  - Being replaced by official Fedora Koji
  - So that Fedora packagers can submit a scratch build or a normal build
  - Building packages from regular Koji in the RISC-V Koji
  - RISC-V is not gating - the hardware is too slow

- RISC-V as a primary architecture on Fedora?
  - Not in the immediate feature, not available enough
  - Rich's benchmarking from 2023: "single-thread perf is approx 4 times
    slower than we want it to be on the currently available hardware"
  - QEMU is actually worse the real-hardware (i.e. QEMU running on x86,
    emulating RISC-V)
  - Hardware availability: rackable, fast-enough, and available

Q&A:

- Difficult packages:
  - valgrind
  - shim / boot-related stuff (due to the signing involved)
- In some langauges (incl GCC) we don't have great support for RISC-V
  (GCC) - e.g. Vector
    - OCaml: compressed extension (of RISC-V), but it's not efficient
- Hypervisor support - rudimentary
- Can you query what extensions are available on the hardware?
  (`hwprobe` syscall - the official way to get the list)
- Discussion about EDK2/firmware
- Vision Five 2 - ACPI, SMBIOS, etc
- Rich:
  - "We're trying to make RISC-V as close as possible to x86 - that's
    our vision (may differ from RIV's vision)"
  - "We want it to be as boring and dull as possible"