[TCWG-1368] Tracked down libfuzzer buildbot failures on aarch64 and raised PR
[TCWG-1424] Use profile information for size optimisation
- Decided to use clang's 2-stage PGO build as next experiment with
compile times on the full test suite as the performance benchmarks
- Spent rather too much time trying to inject an extra c-flag into the
right stage of the bootstrap builds. As a consolation I know a little
bit more about the bootstrap builds.
- Just measuring code size the profile guided feedback builds of clang
are roughly 33% larger than standard clang, with cold functions
optimised for size this drops to 25% larger. Still waiting for
performance figures for all runs. It is looking like in its current
formulation the size optimisation might offer most of the benefits of
PGO but with a lower code size impact. It misses the original goal of
keeping the performance of non-PGO optimisation but lower overall
size.
[Misc] Tracked down a LLD static build failure with a recent glibc.
Looks like it won't affect Arm and AArch64 as it is related to X86
relaxed got relocations to ifunc resolvers.
Planned absences
- Holiday Monday 9th July
Progress:
* VIRT-65 [QEMU upstream maintainership]
+ softfreeze-related maintenance work
+ investigating reported bug with CMSDK timer device model:
couldn't reproduce hangs, but sent patches which fix
various issues
+ code review:
- various patches by the Outreachy/GSoC interns for
the v6M/microbit work
- a few OSX UI bugfix patches
+ scrub through some recently filed bugs to see what might be
worth investigating before the release
+ first pass through KVM Forum talk submissions
thanks
-- PMM
=== Work done during this week ===
* PR85434 / CVE-2018-12886 / TCWG-1379 (stack-protector failure on GCC
ARM): external review
+ finish testing and patch clean up (comments + changelog) and
submit for external review
* Continue work on TCWG-1428 (Support arithmetic on FileCheck regex variable):
+ finish implementation, fix compile issues and debug errors found
on simple testcase
+ run regression testsuite and fix another issue
+ start cleaning up patch
* Misc improvement to jenkins infrastructure
* Misc:
+ gave presentation on stack protector bug
https://docs.google.com/presentation/d/1ksqK-eTYjYhFXlTyVaPA2VIvCTsxwO5Xw-G…
+ Future of microprocessors presentation by Sophie Wilson
=== Plan for week 28 ===
* TCWG-1428 (Support arithmetic on FileCheck regex variable): submit
for external review
+ finish adding comments
+ add documentation and testcase
* Start looking into MCF branch prediction overload due to too many
consecutive branches
SVE Support ([VIRT-198])
========================
- wrote up [post on SVE development] with QEMU for for Linaro Blog
- originally planned to publish on QEMU 3.0 release
- HPC team would like it published before their workshop on 26th
July
- write up a abstract for HPC workshop and plan remote time :todo
[VIRT-198] https://projects.linaro.org/browse/VIRT-198
[post on SVE development]
https://docs.google.com/document/d/15v1asqk-6de2RtA7ZWdIQ29PkY92gl3nlwG7_Se…
RISU Support for SVE ([VIRT-199])
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- CLOSING NOTE [2018-07-06 Fri 12:37]
Changes merged upstream. Ticket closed.
- generated more traces at different VQ's
- VQ3 (found one error, actually x86 SIGFPE issue)
- VQ16 (found 2 errors in ptrue)
- initial run included errors in whilelo, whilels, wrffr, zip[12]
which went away
- I've parked the tests from ASL work pending legal feedback
[VIRT-199] https://projects.linaro.org/browse/VIRT-199
SVE Reviews
~~~~~~~~~~~
- started reviewing {RFC PATCH 00/16} KVM: arm64: Initial support for
SVE guests Message-Id:
<1529593060-542-1-git-send-email-Dave.Martin(a)arm.com>
QEMU ARMv8.3 Support ([VIRT-241])
=================================
- added remaining v8.1 stories to JIRA and re-organised under
- [ARMv8.1 Mandatory Features] and [ARMv8.1 optional features]
- pondering how much effort to do VHE
- it's mostly conditional re-direction of EL1/EL2 registers so
host kernel can pretend it's in EL1 when really in EL2
- some EL2 registers present slightly different formats when VHE
bit is set
[VIRT-241] https://projects.linaro.org/browse/VIRT-241
[ARMv8.1 Mandatory Features]
https://projects.linaro.org/browse/TCWG-1434
[ARMv8.1 optional features] https://projects.linaro.org/browse/TCWG-1435
Upstream Work ([VIRT-109])
==========================
- posted {PATCH v3 00/20} Travis, Code Coverage and Cross Build
updates Message-Id: <20180702143021.18864-1-alex.bennee(a)linaro.org>
- posted {PULL 00/20} Travis, Code Coverage and Cross Build updates
Message-Id: <20180703101444.23778-12-alex.bennee(a)linaro.org>
- with a follow-up of {PULL v2 00/20} Travis, Code Coverage and
Cross Build updates Message-Id:
<20180704090642.3469-1-alex.bennee(a)linaro.org>
- and {PULL v3 00/20} Travis, Code Coverage and Cross Build updates
Message-Id: <20180705160329.30386-1-alex.bennee(a)linaro.org>
- now merged \o/
[VIRT-109] https://projects.linaro.org/browse/VIRT-109
Testing and CI
==============
- spoke with LAVA team about build status and build button
- now have a qa-reports account to submit LAVA jobs via
QEMU CI Loop ([VIRT-187])
~~~~~~~~~~~~~~~~~~~~~~~~~
- investigating porting existing RISU tests via qa-reports
- add additional test patterns :todo
[VIRT-187] https://projects.linaro.org/browse/VIRT-187
KVM CI Loop ([VIRT-2])
~~~~~~~~~~~~~~~~~~~~~~
- need to sync-up on the current state of this work :todo
- started looking at Xiang's latest auto setup scripts
[VIRT-2] https://projects.linaro.org/browse/VIRT-2
[our wiki] https://wiki.linaro.org/Core/Virtualization
MTTCG tests ([VIRT-52])
~~~~~~~~~~~~~~~~~~~~~~~
- need to dust these off and get up-streamed if I'm going to add new
tests :todo
[VIRT-52] https://projects.linaro.org/browse/VIRT-52
Other Tasks
===========
- Spoke to Ilias Apalodimas (LEDGE SIG) about VM networking
- options for zero copy guest to guest networking
- experiments with userspace networking stacks
- lightweight VM+containers
- [Kata Containers] - follow on from Clear Containers work
- Crostini/[CrosVM] work, ChromeOS VM+Docker approach
- Create an Instrumentation EPIC :todo
[Kata Containers] https://katacontainers.io/
[CrosVM] https://chromium.googlesource.com/chromiumos/platform/crosvm/
Completed Reviews [5/5]
=======================
{PATCH v2 00/13} iommu: support txattrs, support TCG execution, implement TZ MPC
Message-Id: <20180604152941.20374-10-peter.maydell(a)linaro.org>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- CLOSING NOTE [2018-06-14 Thu 19:27]
Looks good.
{PATCH 0/8} Docker improvements
Message-Id: <20180628164643.9668-1-f4bug(a)amsat.org>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- CLOSING NOTE [2018-06-29 Fri 21:38]
Grabbed some patches, commented on others
{Qemu-arm} {PATCH v6 00/35} target/arm SVE patches
Message-Id: <20180627043328.11531-1-richard.henderson(a)linaro.org>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- CLOSING NOTE [2018-06-29 Fri 21:39]
Looks good
{Qemu-devel} {PATCH v5 00/35} target/arm SVE patches
Message-Id: <20180621015359.12018-1-richard.henderson(a)linaro.org>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- CLOSING NOTE [2018-06-29 Fri 21:39]
Looking good, stopped to move to v6
{PATCH 0/4} KVM: arm64: FPSIMD/SVE fixes for 4.17
Message-Id: <1528976039-25826-1-git-send-email-Dave.Martin(a)arm.com>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- CLOSING NOTE [2018-06-29 Fri 21:40]
Seems sane to me.
Absences
========
- YVR18 Connect (17th-21st September 2018)
- KVM Forum 2018 (24th-26th October 2018)
Current Review Queue
====================
* {RFC PATCH 00/16} KVM: arm64: Initial support for SVE guests
Message-Id: <1529593060-542-1-git-send-email-Dave.Martin(a)arm.com>
* {Qemu-devel} {RFC v2 0/2} Add BPF suuport to Qemu
Message-Id: <20180625110706.23332-1-sameeh(a)daynix.com>
* {PATCH v4 00/19} reverse debugging
Message-Id: <20180528071332.9424.27343.stgit@pasha-VirtualBox>
* {RFC PATCH 00/12} tests/tcg: Add TriCore tests
Message-Id: <20180501142222.19154-1-kbastian(a)mail.uni-paderborn.de>
* {PATCH 0/4} tests/vm: various trivial fixes
Message-Id: <20180628153535.1411-1-f4bug(a)amsat.org>
* {PATCH 0/6} docker: Port to Python 3
Message-Id: <20180627021423.18404-1-ehabkost(a)redhat.com>
--
Alex Bennée
== Progress ==
* FDPIC
- GCC patch series: updating patches.
- uclibc-ng: discussing problem with lib symbols not being weak.
It's not a blocker for FDPIC anyway. Continued to update/clean the
patch series before submission.
* GCC upstream validation:
- looking at some random noise in testing
- reported a couple of regressions
* Infrastructure:
- patch reviews
- cleanup/improvements
* misc (conf-calls, meetings, emails, ....)
== Next ==
* FDPIC: uclibc-ng, GCC
* GCC upstream validation
o One day off
o LLVM bots
* Troubleshot sanitizers regressions on ARM
o LLVM Machine Outliner on ARM
* Rebased prototype on upstream developments
* Reviewing upstream patch on intra-procedure-call
scratch register handling.
* Investigating potential issues w/r to pass ordering
o Misc
* Various meetings and discussions.
[VIRT-198 # QEMU: SVE Emulation Support ]
Full aarch64-linux-user patch set merged.
[VIRT-214 # SVE System Registers ]
Implemented ID_AA64PFR0_EL1, ID_AA64ZFR0_EL1.
[VIRT-249 # SVE System Mode ]
Fixed sve disabled exception routing.
A booted kernel recognizes sve is present, according to /proc/cpuinfo.
However, the kernel crashes as soon as the first sve insn is executed.
Task for next week is to find out why.
r~
