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RISE TSC Meeting Notes

RISE TSC Meeting Notes

March 20, 2025

Security Software WG Deep-Dive: Robin Randhawa

Timeline of Events (or the story thus far)

  • This is the first Security SW WG Deep Dive to the RISE TSC

  • This is a relatively new Working Group

    • Justification for the WG first pitched to the RISE TSC in June 2024

    • Generally unanimous support

    • Working Group created in August 2024

    • First WG Kick-off meeting in September 2024

    • Monthly meets since then

  • The story arc that has evolved since the WG’s inception

    • Initially: “Security is broad: What is it that we want to do ?”

    • Then: “Let’s look at all the security specific RVIA specs that are frozen/ratified”

    • Then: “Let’s focus on security for embedded first! No! Datacenter/enterprise first!”

    • Then: “Let’s find a common feature subset between embedded and the rest”

    • Then: “Let’s focus on embedded first but choose work that enables the rest too”

    • Finally: “Here’s a break-down of the work we need to do first, let’s talk”

Current Status: OP-TEE for RISC-V Work Definition in Progress

Next Steps

  • Complete OP-TEE/OpenSBI work definitions

    • Get reviews done by key stakeholders (Firmware/SecSW WGs)

    • Post review - translate to RISE WG work packages

    • Nominate work package owners

    • Produce RFPs for suitable work to rope in contractors

  • Bring in focus beyond embedded

    • Undergo a similar consensus driven work identification exercise

      • Areas

        • CoVE enablement

          • Qemu, OpenSBI, CoVE RDSM

    • Build work package definitions, get them reviewed

    • Nominate owners, produce RFPs

What has worked well

  • Good, gradual convergence of opinions towards common goals

  • Good cross WG collaboration!

    • Credits

      • Anup Patel (VentanaMicro)

      • Sunil VL (VentanaMicro)

      • Tim Ouyang (AndesTech)

      • Alvin Chang (AndesTech)

      • Ravi Sahita (Rivos)

      • Peter Lin (SiFive)

What has not worked well

  • Everyone is busy!

    • Hard to get timely responses generally speaking

    • Need to constantly push and prod folks…

  • More mailing list interactions needed

    • General tendency to leave discussions until WG monthly meets

    • Will try hard to change this!

  • More enthusiasm needed!

    • Not enough folks attending monthly WG meets

    • Security is a generally dry topic, yes, but it is super important!!!

Mar 13, 2025

RISE Developer Infrastructure Deep Dive- Paul Walmsley

Topics

  • Developer Infrastructure WG Introduction & Vision

  • Build Farm

    • Introduction

    • Value

    • 2024Q4 Review

    • 2025Q1 Review

  • Board Farm

  • Developer Tools

  • Looking Forward to 2025Q2

  • Credits

Developer Infrastructure WG Introduction

  • Charter

    • The Developer Infrastructure WG focuses on software and services to support open-source RISC-V developers - both RISE members and the broader open-source community.

  • Co-chairs

    • Barna Ibrahim (Rivos)

    • Paul Walmsley (SiFive)

  • TSC Chair Contact

    • Nathan Egge (Google)

Developer Infrastructure WG Vision

  • Three mutually-supporting projects

    • RISE Build Farm (Active)

    • RISE Board Farm (Inactive)

    • RISE Developer Tooling (Active)

  • Goal

    • Provide robust development infrastructure and tools to RISC-V developers

RISE Build Farm: Introduction

  • Objective

    • Cross-build and test (in simulation) RISC-V ports of key open source software

  • Running in Hetzner Cloud (new!)

  • Björn Töpel (Rivos) coordinating

  • Brian “Redbeard” Harrington (Red Hat): co-admin

  • Status

    • Eight active projects 

      • ~22 active large VM instances on Hetzner Cloud

      • Mostly acting as Github Runner performing cross-compilation/qemu-system-riscv{32,64} tests

Build Farm: Value

  • Thousands of builds, and millions of tests per month on key, foundational RISC-V open source projects

    • GCC, LLVM, Linux kernel, GLIBC, Python

  • > 150 toolchain bugs found via our fuzzer instances

  • Jeff Law/Ventana (and upstream GCC maintainer)

    • “We don’t commit anything into gcc for RISC-V that hasn’t passed the RISE gcc CI.  Incredibly helpful!” 

Build Farm: 2024Q4 Review 

  • Eight existing projects running

    • RISE GCC pre-commit CI (Patrick O'Neill, Edwin Lu)

    • RISE GCC post-commit CI (Patrick O'Neill, Edwin Lu)

    • RISE GCC fuzzer CI (Patrick O'Neill, Edwin Lu)

    • RISE GCC microcontroller CI (Patrick O'Neill, Edwin Lu)

    • RISE GLIBC pre-commit CI (Patrick O'Neill, Edwin Lu)

    • RISE LLVM fuzzer CI (Patrick O'Neill, Edwin Lu)

    • RISE Linux Kernel CI (Björn Töpel)

    • RISE Python Wheels (Mark Ryan)

  • Two existing projects temporarily expanded

    • RISE GCC fuzzer CI (Patrick O'Neill, Edwin Lu)

    • RISE LLVM fuzzer CI (Patrick O'Neill, Edwin Lu)

    • Remaining GCP credits leveraged to greatly expand the number of fuzzer instances running (and thus the number of bugs we could find)

      • Thanks to Patrick, Edwin, and Björn for putting in extra work to make this possible!

  • One existing project shut down

    • RISE QEMU Aarch64 test system (Paul Walmsley, Max Chou)

      • No longer needed by RP005

 

 

  • Considerable volunteer time spent preparing for the Hetzner transition and monitoring LF/Hetzner progress

  • Google Cloud account closed out with ~$10,000 USD of credits unused (preserved as a safety margin)

    • All credits expired December 31, 2024

      • Thanks again to Google for the donation

  • Hetzner account was not set up in time to complete the server transition before the end of the year

    • RISE incurred some direct budget costs in 2025Q1

      • Discussed in following slides

  • Ran on GCP throughout January as we waited for the Hetzner account to be set up

    • Toolchain fuzzer instances temporarily shut down to reduce costs (non-critical services)

    • Required direct payment from RISE budget, as GCP credits expired EOY 2024

  • Migrated to new Hetzner infrastructure at the end of January

    • Fast execution saved RISE money

    • Credits

      • Björn Töpel (Rivos), Patrick O’Neill (Rivos), Edwin Lu (Rivos), Mark Ryan (Rivos)

      • Brian “Redbeard” Harrington (Red Hat)

  • Some challenges with the Google Cloud->Hetzner transition

    • Hetzner account not available for our use until end of January

      • Two month latency from when we requested it

    • Unplanned 30 hour outage at the end of February

      • Caused by a billing dispute

      • Adding external monitoring to catch outages sooner

    • Hetzner account migration at the beginning of March

      • Original Hetzner account not set up to bill in Euros

      • New account had to be created and instances migrated

  • No ability for RISE to directly track expenditures on Hetzner

    • Our accounts do not have these permissions

    • Going forward, these deep dives will not include budget reports

  • Two existing projects temporarily paused in January

    • RISE GCC fuzzer CI (Patrick O'Neill, Edwin Lu)

    • RISE LLVM fuzzer CI (Patrick O'Neill, Edwin Lu)

  • One existing project expanded (as planned)

    • RISE Linux Kernel CI (Björn Töpel)

      • Doubled the number of servers to provide additional test coverage

RISE Board Farm

  • Objective

    • Provide a range of Linux-capable RISC-V boards to run functionality and performance tests on CI-generated code

    • Investigate feasibility of providing developer access to boards

  • Status

    • No significant progress in 2024Q4 or 2025Q1

      • Build Farm relocation and emergency response taking up all available management bandwidth

    • Planning to ramp up in 2025Q2

    • Volunteers solicited!

RISE Developer Tools

  • Objective

    • Provide a full Linux system image build, boot, and development environment for use on both simulators (QEMU) and RISC-V hardware

      • Ideally combines cross and native development environment and native system software and userspace

  • Status

    • Nathan’s Gentoo build available for general use with cutting-edge software included

      • Luca Barbedo putting in a lot of effort here

    • How to productize/test?

Credits

  • Barna Ibrahim (Rivos): Co-chair

  • Björn Töpel (Rivos): Kernel CI Build Farm Project Admin, Build Farm Lead

  • Brian ‘redbeard’ Harrington (Redhat): Build Farm Administrator

  • Edwin Lu (Rivos): Toolchain Build Farm Project Admin

  • Mark Ryan (Rivos): Python Build Farm Project Admin

  • Nathan Egge (Google): TSC contact, Developer Tools Lead

  • Patrick O’Neill (Rivos): Toolchain Build Farm Project Admin

  • Paul Walmsley (SiFive): Co-chair

Mar 6, 2025

Deep Dive Language Runtimes - Ludovic HENRY

  • Status Update: Java

    • Support for Vector extension: continual work

      • Support for FP16, more compiler optimizations

    • Matching RVA23:

      • Added: Zicond, Zfa, Zvkt, Zvbb

      • Only missing: Zimop, Zcmop, Zcb, and Zawrs

  • Status Update: Go

    • Matching RVA23:

      • It’s a work-in-progress

      • Adding C, V, B, Zicond, Zfa, Zihintpause, Zihintntl, Zcb, Zvbb, Zawrs

    • RP001

      • Wiki is up-to-date to track work to be done

  • Status Update: Python

 

  • Please comment on mailing list for prioritization

    • Anything not listed you’d like to see?

    • Anything not as high on the priority list as you expected?

 

Deep Dive Compilers/Toolchains – Jeff Law

  • Apologies for last week, customer meeting I couldn’t miss

  • RP007

    • Hoping to see upstream engagement on what they’re finding/fixing 

  • RP008

    • making great progress on finding real issues and either fixing them or getting them recorded for future work

 

  • Not sure if anyone has put their name in the hopper for leading the group.  I expect my bandwidth to be limited going forward, though could probably help cover GCC if absolutely necessary

 

  • GCC– GCC 15 release cycle in progress, ETA May 1

    • Still fixing bugs, but nothing RISC-V specific that is particularly worrisome

    • Many optimizations across scalar and vector domains

      • CRC work was finally integrated

      • Cactu optimization work

      • Vector, emphasis on x264 perf and zvl128..zvl512

      • Function multi-versioning

      • Stack-clash mitigation

  • Items for 2025

    • Xz vectorization.  POC shows ~12% on spec. 

    • Another round of Zbs & extension removal improvements, 

    • Fusion work (significant fixes, new cases, discovery)

    • Uarch support for vector costing/tuning

 

  • LLVM – LLVM 20 release imminent

    • No major RISC-V specific concerns for release according to Philip & Craig

    • Stack clash mitigations have been integrated

    • Function Multi-versioning

    • Vectorize xz search loop

  • Items for 1H2025

    • Folding “addi” into loads/stores more aggressively (done)

    • Shrink wrapping development done, just working through review comments

    • Landing pads for CFI (in flight)

    • Improvements for x264 vectorization, more work to be done

Feb 20, 2025

Deep Dive Simulator Emulator- Daniel Barboza

  • SE_02_004 (RP005) - QEMU RVV performance enhancements

    • Development completed, reviews ongoing in the ML. Performance enhancement up to 500% depending on vector configuration and workload

    • Link to last report 

  • SE_01_021 - QEMU RVA23 profile support

    • Queued in the maintainer’s tree

    • Prerequisite of other items such as “RISC-V Server SoC Reference Board”

  • E-trace items (SE_01_024, SE_01_025, SE_01_026, SE_01_027)

    • New in 2025. Implementation of RISC-V Efficient Trace spec. Owner: Daniel Barboza (Ventana Micro)

    • Development ongoing

  • Other items under review in the QEMU mailing list:

    • SE_01_003 - QEMU WorldGuard support

    • SE_01_004 - QEMU IOPMP support

  • SE_01_022 - RISC-V Server SoC Reference Board

  • SE_01_005 - QEMU PCIe passthru on x86 hosts

  • SE_01_023 - QEMU RISC-V IOMMU Enhancements

  • Not yet sent for review

    • SE_01_022 - QEMU P Extension support

  • Items completed

    • SE_01_017 - QEMU ACPI SPCR Support for RISC-Vc

Feb 6, 2025

Kernel and Virtualization Deepdive- Anup Patel

What’s merged for Linux-6.14 ?

  • Linux-6.14-rc1 was released on 2nd February 2025

  • Noteworthy stuff merged for Linux-6.14:

    • Linux RISC-V

      • T-Head vector extensions support

    • KVM RISC-V

      • Svvptc, Zabha, and Ziccrse extension support for Guest/VM

      • Virtualize SBI system suspend extension for Guest/VM

      • Trap related exit statistics as SBI PMU firmware counters for Guest/VM

 

RVA23 profile: Discovery updates

  • HWPROBE additions in Linux-6.14

    • No updates

  • KVM ONE_REG additions in Linux-6.14

    • Zabha, Svvptc, and Ziccrse

  • Kernel HWPROBE (27-01-2024, wiki)

    • TBD - 7 (7.45%), NA - 47 (50%), COMPLETED - 40 (42.55%), TOTAL - 94

  • KVM ONE_REG (27-01-2024, wiki)

    • TBD - 24 (25.53%), NA - 13 (13.83%), COMPLETED - 57 (60.64%), TOTAL - 94

 

 

2024-1H: Project updates

  • 2024-1H: Recently upstreamed projects

    • LK_03_023 - QEMU-KVM Zawrs support

    • LK_02_025 - KVM System Suspend Virtualization

    • LK_03_008 - QEMU-KVM AIA user-space irqchip_split support

  • 2024-1H: Development status (27-01-2025, wiki)

    • TBD - 2 (4.08%), ONGOING - 1 (2.04%), COMPLETED - 46 (93.88%), TOTAL - 49

  • 2024-1H: Upstreaming status (27-01-2025, wiki)

    • TBD - 3 (6.12%), ONGOING - 5 (10.21%), COMPLETED - 41 (83.67%), TOTAL - 49

 

2024-2H: Project updates

  • 2024-2H: Recently development complete projects

    • LK_01_024 - Supervisor Counter delegation (Smcdeleg and Ssccfg) based perf

    • LK_01_025 - Control Transfer Record (Smctr and Ssctr) support in perf driver

    • LK_01_044 - Firmware Feature support

    • LK_01_045 - Message Proxy support

    • LK_01_046 - RPMI Clock driver using SBI MPXY

    • LK_02_028 - KVM Firmware Feature virtualization

    • LK_03_026 - KVMTOOL Svadu support

    • LK_03_034 - KVMTOOL Smnpm and Ssnpm support

  • 2024-2H: Recently upstreamed projects

    • LK_02_027 - KVM Svvptc virtualization

  • 2024-2H: Development status (27-01-2025, wiki)

    • TBD - 13 (35.14%), ONGOING - 1 (2.70%), COMPLETED - 23 (62.16%), TOTAL - 37

  • 2024-2H: Upstreaming status (27-01-2025, wiki)

    • TBD - 18 (48.64%), ONGOING - 13 (35.14%), COMPLETED - 6 (16.22%), TOTAL - 37

Jan 30, 2025

Distro and Integration-  Brian Harrington

The most recent discussion revolved around the development of a unified database for RISC-V processors and related tools, aiming to streamline information access and collaboration within the community. Additionally we discussed some needs/desired with regards to automated builders (specifically hosted by GitHub/GitLab). Here's a structured summary of the key points:

  1. RISC-V Unified Database:

  1. Related Items:

  • Reminder of https://riscv.builders , building / compiling software for RISC-V, though called out that it’s still insufficient for the u-boot development desired by members.

  • Nathan Egge provided a PDF about LLVM-Mingw, detailing its use for cross-compiling RISC-V applications on Windows, which is crucial for developers in Windows environments.

 

Jan 23, 2025

System Libraries Deep Dive- Nathan Egge

Multimedia (and other) RVI extensions

  • Feedback from VideoLAN community fed into RVI proposals

    • dot prod, vector abs-diff (SAD), zip/unzip

  • Continued collaboration after VDD 2024

    • Got feedback on signed variants of SAD extension proposal

    • Plan to set up meeting across RISE, RVI Vector SIG and VideoLAN / FFmpeg

    • Goal: early feedback on algorithms instructions would be used in

      • May guide instruction coding (params) and find edge cases *before* ratification 

  • RISE presence at FOSDEM 2025

    • Attend RISC-V devroom (thanks Bjorn)

    • Concurrent open-media devroom for in person collaboration

  • Community still asking for more diverse hardware

    • Larger VLEN, OOO cores, different IP to cross validate algorithms

 

Software Optimization Progress

  • XNNPACK still a priority

    • Ken Unger (Microchip) patches in flight quantized kernel optimizations for RVV

  • PyTorch progress

    • Philip Reams (Rivos) open to collaborating and providing public RISC-V packages

    • Build system issues discussed

  • sleef build issues

    • Currently broken for cross-compilation, not an easy fix

  • New project hosted on RISE gitlab for Mbed-TLS

 

Developer Images

  • Luca Barbato (Gentoo) sent a ROMA II laptop for testing

    • Working to get this booting to check status of graphics stack

  • clang-20 released, contains some fixes for auto-vectorization

    • Need to check if this allows zvl256b

  • gcc progress made fixing issues raised by Luca, but not ready yet

  • Minor issues with rustc ebuild on RISC-V addressed by Luca

 

System Libraries Priorities - H1 2025

  • High profile, in-demand projects, e.g., Tensorflow, Chromium, etc.

    • Planning to finalize this in next System Libraries meeting Dec 10, 2024

  • Instructio timings for optimization guide

    • Potential to use llvm-exegesis to extract these for help with RVV optimizations

  • Capture missing vector instructions from multimedia projects [1]

    • Key Idea: Collect gaps in extension opcodes preventing efficient multimedia DSP functions, e.g., no transpose op, no dotprods, missing sign-unsign mults, etc.

    • Work with multimedia developers

  • Testing framework for upstream projects

    • Issues raised by vendors and OSS contributors about inconsistent benchmarking

    • Example project + source code with best practices for statistically significant data

  • More guest speakers!

2025

 

Dec 5, 2024

System Libraries Deep Dive

System Libraries Priorities - H1 2024

Developer Images

  • Latest image based on Bianbu 2.0 and can be found here [1]

  •  

    • Boots Banana Pi BPI-F3 and possibly other k1/m1 based boards

    • Clang-19.1.2

  • Past experiments results

  •  

    • clang-20 snapshots fail to build [2]

    • gcc-15 still has problems, but it is reported that gcc-trunk has the alignment problems fixed.

    • The rust build system seems to fail to pick the Gentoo cross compiler put in config.toml (I'll investigate further why)

  • Presented these images at the RISC-V 101 session and RVI devboard sig [3]

[1] https://dev.gentoo.org/~lu_zero/riscv/gentoo-linux-k1_dev-sdcard-2.0.img.xz 

[2] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115789

[3] https://people.videolan.org/~negge/riscv101.pdf 

Proposed RVV instructions for Multimedia



Limited usage of register based vsetvl is OK

  • Optimization guide cautions against using vsetvl

  • Long discussion with hardware engineers at LLVM Dev Meeting Santa Clara

  •  

    • Under some circumstances it is OK to use vsetvl, e.g., as in dav1d

    • May be possible to use this in auto-vectorization loop unrolling to “fold” the tail so it shares the same code as main body, potentially reducing cost of enabling RVV

Register Pressure Example - 16bpc blend

Recall…

  vwmulu.vv v24, v8, v16

  vwmulu.vv v8, v12, v20

Section 5.2 Vector Operands

System Libraries Priorities - H1 2025

  • High profile, in-demand projects, e.g., Tensorflow, Chromium, etc.

  •  

    • Planning to finalize this in next System Libraries meeting Dec 10, 2024

  • Instruction timings for optimization guide

  •