Hello,
# [GNU-767] Support changing SVE vector length in remote debugging
* Got prototype of variable length vectors in GDB target descriptions
barely working, but fell down a rabbit hole trying to fix an issue
with the vector register size being misreported by ‘sizeof()’. Decided
to change tack and implement the simpler aim of updating the client
and server target descriptions in sync when the vector length changes.
This is Luis' idea from 2020¹, and closer to how native GDB debugging
currently works in this scenario.
--
Thiago
¹ https://sourceware.org/pipermail/gdb/2020-January/048341.html
Progress:
* UM-2 [QEMU upstream maintainership]
+ Finished sorting out the exynos4210 SoC interrupt wiring and sent
a patchset that cleans it up and makes it stop using qemu_split_irq()
+ rc3 tagged this week. We will need an rc4 next week for a couple of
late-breaking security fixes.
* QEMU-420 [GICv4 emulation]
+ Finished the last bits of debugging and wiring up GICv4 support on
the virt board, and sent initial patchset to the list for review:
https://patchew.org/QEMU/20220408141550.1271295-1-peter.maydell@linaro.org/
-- PMM
Hello,
# [GNU-767] Support changing SVE vector length in remote debugging
* Moved tracking of this work from GNU-732 (GDB support for SME) to
more specific story GNU-767.
* Started writing prototype of variable length vectors in GDB target
descriptions.
# Basic setup / onboarding
- Read a couple more Linaro processes documents.
# Misc
* Attended Linaro Connect Tech Day: Core Technologies.
--
Thiago
Project Stratos
===============
- more follow-up on Re: Understanding osdep_xenforeignmemory_map mmap
behaviour Message-Id:
<alpine.DEB.2.22.394.2203231838130.2910984@ubuntu-linux-20-04-desktop>
- various Stratos sync-ups
vhost-device maintainer effort ([UM-196])
- bit of maintainer review work
Linux RPMB Sub-system and virtio-driver ([STR-40])
- got [kernel] and [vhost-user] daemon passing all tests with
multi-block reads/writes
- will clean-up series next week for posting to the lists
[STR-40] <https://linaro.atlassian.net/browse/STR-40>
[kernel]
<https://git.linaro.org/people/alex.bennee/linux.git/tag/?h=testing/vrpmb-re…>
[vhost-user]
<https://github.com/stsquad/qemu/tree/virtio/vhost-user-rpmb-v2>
QEMU Upstream Work ([UM-2])
===========================
- posted [PATCH v1 0/2] some tests and plugin tweaks for SVE
Message-Id: <20220328152614.2452259-1-alex.bennee(a)linaro.org>
- posted [PATCH v3] tests/avocado: update aarch64_virt test to
exercise -cpu max Message-Id:
<20220328161357.2464572-1-alex.bennee(a)linaro.org>
- posted [RFC PATCH] docs/devel: add some notes on the
binfmt-image-debian targets Message-Id:
<20220329095041.2758355-1-alex.bennee(a)linaro.org>
[UM-2] <https://linaro.atlassian.net/browse/UM-2>
Other
=====
- Presented [LTD 2022 QEMU talk]
- attneded some others
[LTD 2022 QEMU talk]
<https://resources.linaro.org/en/resource/tL9M2yyti73StqK1d9ap8f>
Completed Reviews [1/1]
=======================
[PATCH 00/15] tests/docker and tests/tcg cleanup and diet
Message-Id: <87czi6xbzo.fsf(a)linaro.org>
Absences
========
Current Review Queue
====================
TODO [PATCH 00/17] tests/docker and tests/tcg cleanup and diet
Message-Id: <20220401141326.1244422-1-pbonzini(a)redhat.com>
========================================================================================================================
TODO [RFC PATCH 0/6] softfloat 128-bit integer support
Message-Id: <20220328201442.175206-1-matheus.ferst(a)eldorado.org.br>
=========================================================================================================================
TODO [PATCH for-7.1 v2 00/39] Logging cleanup and per-thread logfiles
Message-Id: <20220326132534.543738-1-richard.henderson(a)linaro.org>
=======================================================================================================================================
--
Alex Bennée
Progress (short week, 2 days):
* UM-2 [QEMU upstream maintainership]
+ More of the usual freeze-related work
+ Tracked down and fixed assertion when running with clang sanitizers
+ We finally got a Coverity Scan run through for the first time in a
month or two, and it was full of new issues. Spent some time going
through them and marking false positives or reporting the problems
back to original code authors to be fixed
+ Looking at the tangle of interrupt lines in our exynos4210 SoC
model -- this needs a refactoring and cleanup so we can get rid
of its uses of an obsolete function
-- PMM
Hello,
# [GNU-732] GDB support for ARMv9 Scalable Matrix Extension (SME)
* Continued working on gdbserver and remote protocol support for
programs that change the SVE vector length during execution:
- Studied the 2020 discussion around Luis' proposal to support changed
VL size in the Remote Serial Protocol / gdbserver, as well as
relevant parts of the RSP itself.
- Started studying GDB's type system and how it handles dynamic types,
and also the target description code to assess the feasibility of
making the vector registers use a dynamically sized type.
- Luis made a second proposal in that mailing list discussion where
the target description wouldn't be transferred via the remote
protocol, just the vector length. Then both GDB and gdbserver could
locally update their own descriptions based on that. Starting to
think about this alternative. It would probably be simpler than
changing the target description to use a dynamically sized type for
the Z registers.
# Basic setup / onboarding
* Work laptop arrived. Set it up.
--
Thiago