- linaro-toolchain - lists.linaro.org

by Thiago Jung Bauermann

Hello, # [GNU-767] Support changing SVE vector length in remote debugging - Continued working on new approach to support changing SVE vector length in remote debugging. # TCWG CI - Analysed GCC regression GNU-880 which is actually an XFAIL → XPASS so I sent a patch removing the xfail annotation. - Analysed GCC regression GNU-881. The problem is that we don't have Python in the ABE sysroot so a new Python GCC plugin testcase fails to build. Sent a patch to detect that situation and mark the test as unsupported. It was committed upstream. - Tested a couple of new versions of a GDB mailing list patch to see if it fixed the failure reported by the precommit CI. Reported results to patch author. - Fixed silly mistake spotted by Laurent in ABE Gerrit requests to use TIMEOUTFACTOR for DejaGnu testsuites. Adjusted it to not use the factor in GDB on armhf and sent new version for review. - Reviewed a couple of Gerrit requests. -- Thiago

2 years, 8 months

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[ACTIVITY] report week ending 18 Aug

by Peter Maydell

Progress (short week, 3 days): * UM-2 [QEMU upstream maintainership] - sent out another couple of "avoid VLA" patches * QEMU-530 [QEMU ARM v9.4 Baseline CPU for TCG] - managed to write some first-pass code for the MTE checks for FEAT_MOPS memset operations. Got something together enough to send to RTH for some pre-review before I roll the approach out to the other insns. -- PMM

2 years, 8 months

1
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Re: [Linaro-TCWG-CI] Failure after gcc commit: basepoints/gcc-14-3309-g360cabf45a0 arm: Add define_attr to to create a mapping between MVE predicated and unpredicated insns

by Maxim Kuvyrkov

Hi Stamatis, Let us know if you need any help in troubleshooting the failures in https://patchwork.sourceware.org/project/gcc/list/?series=23558 . Kind regards, -- Maxim Kuvyrkov https://www.linaro.org > On Aug 18, 2023, at 01:13, ci_notify(a)linaro.org wrote: > > [Linaro-TCWG-CI] Failure after gcc commit: basepoints/gcc-14-3309-g360cabf45a0 arm: Add define_attr to to create a mapping between MVE predicated and unpredicated insns > > Dear contributor, our automatic CI has detected problems related to your patch. > Please find below some details about it. > > In CI config tcwg_gcc_build/master-arm after: > > | commit 360cabf45a05d5d2d5a98f0e081cb8f53e01e8aa > | Author: Stamatis Markianos-Wright <stam.markianos-wright(a)arm.com> > | Date: Thu Aug 17 11:30:58 2023 +0100 > | > | arm: Add define_attr to to create a mapping between MVE predicated and unpredicated insns > | > | Hi all, > | > | I'd like to submit two patches that add support for Arm's MVE > | Tail Predicated Low Overhead Loop feature. > > Results changed to > # reset_artifacts: > -10 > # true: > 0 > # build_abe gcc: > # FAILED > # First few build errors in logs: > # 00:02:46 /home/tcwg-build/workspace/tcwg_gnu_1/abe/snapshots/gcc.git~master/gcc/config/arm/mve.md:7018:8: error: invalid decimal constant > # 00:02:46 make[2]: *** [Makefile:2647: s-preds-h] Error 1 > # 00:02:46 make[1]: *** [Makefile:4655: all-gcc] Error 2 > # 00:02:46 make: *** [Makefile:1051: all] Error 2 > # 00:02:28 /home/tcwg-build/workspace/tcwg_gnu_1/abe/snapshots/gcc.git~master/gcc/config/arm/mve.md:7018:8: error: invalid decimal constant > # 00:02:28 make[2]: *** [Makefile:2586: s-conditions] Error 1 > # 00:02:28 /home/tcwg-build/workspace/tcwg_gnu_1/abe/snapshots/gcc.git~master/gcc/config/arm/mve.md:7018:8: error: invalid decimal constant > # 00:02:28 /home/tcwg-build/workspace/tcwg_gnu_1/abe/snapshots/gcc.git~master/gcc/config/arm/mve.md:7018:8: error: invalid decimal constant > # 00:02:28 make[2]: *** [Makefile:2647: s-preds-h] Error 1 > # 00:02:28 make[2]: *** [Makefile:2652: s-constrs-h] Error 1 > # 00:02:28 /home/tcwg-build/workspace/tcwg_gnu_1/abe/snapshots/gcc.git~master/gcc/config/arm/mve.md:7018:8: error: invalid decimal constant > # 00:02:28 make[2]: *** [Makefile:2642: s-preds] Error 1 > # 00:02:35 make[1]: *** [Makefile:4655: all-gcc] Error 2 > # 00:02:35 make: *** [Makefile:1051: all] Error 2 > > From > # reset_artifacts: > -10 > # true: > 0 > # build_abe gcc: > 1 > > > > -----------------8<--------------------------8<--------------------------8<-------------------------- > The information below can be used to reproduce a debug environment: > > Current build : https://ci.linaro.org/job/tcwg_gcc_build--master-arm-precommit/1787/artifac… > Reference build : https://ci.linaro.org/job/tcwg_gcc_build--master-arm-build/1060/artifact/ar… > > Reproduce last good and first bad builds: https://git.linaro.org/toolchain/ci/interesting-commits.git/plain/gcc/sha1/… > > Full commit : https://github.com/gcc-mirror/gcc/commit/360cabf45a05d5d2d5a98f0e081cb8f53e… > > Latest bug report status : https://linaro.atlassian.net/browse/GNU-692 > > List of configurations that regressed due to this commit : > * tcwg_gcc_build > ** master-arm > *** Failure > *** https://ci.linaro.org/job/tcwg_gcc_build--master-arm-precommit/1787/

2 years, 8 months

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LLVM bots down for extended period

by Aaron Ballman

Hello! You are the point of contact for some build bots in the LLVM build lab that have been down for an extended period of time. If you're not the correct point of contact, can you please CC the right individual (if you know who they are)? The following bot(s) appear to have been down for multiple weeks: https://lab.llvm.org/buildbot/#/builders/clang-armv7-global-isel https://lab.llvm.org/buildbot/#/builders/clang-native-arm-lnt-perf https://lab.llvm.org/buildbot/#/builders/clang-aarch64-sve-vla-2stage https://lab.llvm.org/buildbot/#/builders/clang-aarch64-sve-vls-2stage https://lab.llvm.org/buildbot/#/builders/clang-aarch64-sve-vls https://lab.llvm.org/buildbot/#/builders/clang-armv7-vfpv3-full-2stage https://lab.llvm.org/buildbot/#/builders/clang-thumbv7-full-2stage Do you have plans to bring the bot back online? If not, that's okay -- just let me know and I can remove the bots from the lab for you. Thank you! ~Aaron

2 years, 8 months

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CMake requirements LLVM buildbots

by Mark de Wever

Hi, As discussed in [1] I just committed [2] to update the minimum CMake version in LLVM to 3.20.0. Unfortunately it seems the ARM builders in the libc++ precommit CI are running CMake 3.16.3 [3]. Would it be possible to update these builders? [1] https://discourse.llvm.org/t/rfc-upgrading-llvms-minimum-required-cmake-ver… [2] https://reviews.llvm.org/D144509a [3] https://buildkite.com/llvm-project/libcxx-ci/builds/19366#0186756a-1599-46e… Thanks, Mark

2 years, 8 months

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[ACTIVITY] Report for week #32

by Thiago Jung Bauermann

Hello, # [GNU-767] Support changing SVE vector length in remote debugging - Returned to implementing support for changing SVE vector length in remote debugging. The patch series I sent earlier this year used an approach that some maintainers weren't enthusiastic about (modifying the Remote Serial Protocol to request XML target descriptions). Now trying the approach they suggested, which is to extend target descriptions to support expressing vector registers whose length is given by the contents of another register. # TCWG CI - Following Maxim's suggestion, sent and merged Gerrit review requests to increase chance of tcwg_gdb_check jobs to be faster at detecting new or newly expired flaky tests: - 45151: tcwg_gdb: Increase job frequency - 45152: round-robin.sh (build_abe): Increase time to re-detect GDB flaky tests - Implemented change in ABE to support glibc's TIMEOUTFACTOR environment variable for DejaGnu testsuites. Testing on armv8l and aarch64. -- Thiago

2 years, 9 months

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[ACTIVITY] week ending Aug. 13 2023

by Alex Bennée

QEMU Upstream Work ([UM-2]) =========================== - posted [PATCH 0/8] some testing and gdbstub fixes Message-Id: <20230810153640.1879717-1-alex.bennee(a)linaro.org> for 8.1 release - posted [RFC PATCH 0/2] linux-user: extend -dfilter to accept paths Message-Id: <20230811162830.2278032-1-alex.bennee(a)linaro.org> [UM-2] <https://linaro.atlassian.net/browse/UM-2> [plugin patch] <https://patchew.org/QEMU/CADc=-s5RwGViNTR-h5cq3np673W3RRFfhr4vCGJp0EoDUxvho…> Completed Reviews [3/3] ======================= [PATCH v3 0/3] Add VIRTIO sound card Message-Id: <cover.1689692765.git.manos.pitsidianakis(a)linaro.org> [RFC v4 00/11] Native Library Calls Message-Id: <20230808141739.3110740-1-fufuyqqqqqq(a)gmail.com> Absences ======== - Birthday long weekend next week Current Review Queue ==================== TODO [PATCH v3 0/9] gfxstream + rutabaga_gfx Message-Id: <20230803235502.373-1-gurchetansingh(a)google.com> ======================================================================================================== TODO [PATCH 0/4] chardev/char-fe: Document FEWatchFunc and use G_SOURCE_CONTINUE/REMOVE Message-Id: <20230705133139.54419-1-philmd(a)linaro.org> ============================================================================================================================================= TODO [PATCH v2 0/3] util/fifo8: Introduce fifo8_peek_buf() Message-Id: <20230705131859.53970-1-philmd(a)linaro.org> ================================================================================================================ -- Alex Bennée Virtualisation Tech Lead @ Linaro

2 years, 9 months

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[ACTIVITY] report week ending 11 Aug

by Peter Maydell

Progress: * UM-2 [QEMU upstream maintainership] - code review, notably: + RTH's setnegcond series + Jean-Philippe's fixes for various FEAT_RME bugs + Akihiko's series to make KVM '-machine none' not default to 40 bits of IPA space if the host doesn't supoprt that (like the Apple CPUs) - sent a patch to catch the illegal exception return case from EL3 with bad SCR_EL3.{NSE,NS} - respin and resend of ptw cleanup patchset - tidied another 'BiteSizedTask' entry into a gitlab issue - went back to an old minor cleanup task: getting rid of the last dozen or so uses of variable-length arrays in the codebase (so we can enforce not using them in the compiler, and avoid unchecked-on-stack-allocation security bugs). Sent patches to zap a few more. * QEMU-530 [QEMU ARM v9.4 Baseline CPU for TCG] - thinking a bit more about FEAT_MOPS and MTE checks, but ultimately not much progress: didn't find enough hours with a sufficiently alert mind... -- PMM

2 years, 9 months

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[ACTIVITY] Report for week #31

by Thiago Jung Bauermann

Hello, # TCWG CI - Implemented increasing testsuite timeout for each testsuite try in GDB check jobs. Sent a Gerrit review request for it but then found out that it makes armhf jobs take a lot longer, so abandoned it. # Community - Finished reviewing SME patches for GDB and gdbserver. -- Thiago

2 years, 9 months

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[ACTIVITY] report week ending 4 Aug

by Peter Maydell

Progress: * UM-2 [QEMU upstream maintainership] - some bits and pieces for release - code review, notably: + raspberry pi 4 support patchseries (a big 44-patch set) + Xilinx Versal CFI support patches * QEMU-530 [QEMU ARM v9.4 Baseline CPU for TCG] - more work on FEAT_MOPS: tested my memset implementation, and fixed various bugs. Still no MTE tag checking support. -- PMM

2 years, 9 months

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[ACTIVITY] Report for week #30

by Thiago Jung Bauermann

Hello, # TCWG CI - CI Babysitting: Worked on two regressions detected at the end of last week. - Enabled precommit testing for GDB patches. # Misc - Reviewing SME patches for GDB and gdbserver. -- Thiago

2 years, 9 months

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[ACTIVITY] report week ending 28 Jul

by Peter Maydell

Progress: * UM-2 [QEMU upstream maintainership] - release related stuff: handling merge requests, etc (now passed back to RTH again) - sent some patches for a few easy coverity issues - worked through some code review (in particular some patches from new contributors) - created a gitlab "bite sized task" issue that better explains and has more detail on the "convert from malloc to g_malloc" suggested task for new contributors * QEMU-530 [QEMU ARM v9.4 Baseline CPU for TCG] - a little more progress with FEAT_MOPS. I now have an untested implementation of the memset insns which I think is complete except for MTE tag checking -- PMM

2 years, 9 months

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[ACTIVITY] Report for week #29

by Thiago Jung Bauermann

Hello, # TCWG CI - Babysat the CI: Investigated 9 regressions in GCC, 2 in GDB, 1 in LLVM and 1 in glibc. Reported 4 in GCC (GNU-855, GNU-857, GNU-858 and GNU-859). 3 of which are fixed and another has a tentative fix. - Reviewed a couple of Gerrit requests. -- Thiago

2 years, 9 months

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[ACTIVITY] report week ending Jul 21

by Peter Maydell

Progress: * UM-2 [QEMU upstream maintainership] - fixed some places in our RTC device models where we were putting a time_t or time_t offset into a 32-bit variable - took over from RTH briefly for pullreq merge handling - sent some patches fixing minor Coverity issues - investigated a couple of "test case fails on big-endian host" errors: sent patches for Sparc FPRS handling and for the Arm SMMUv3 model - Investigated report that our MPS2/3 M-profile models don't have the same number of MPU regions configured as the real FPGA images, and so you can't run the same Zephyr binary on both. Have some preliminary patches to correct the number of regions. * QEMU-530 [QEMU ARM v9.4 Baseline CPU for TCG] - finally got back to FEAT_MOPS work; wrote a skeleton of code for the memset operations that's about right up to the point where it needs to actually do the memset... -- PMM

2 years, 9 months

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[ACTIVITY] week ending Jul. 23 2023

by Alex Bennée

Project Orko ============ - Hosted sprint planning, syncs with EPAM and Xilinx [roadmap] <https://linaro.atlassian.net/wiki/spaces/ORKO/overview> Generic vhost-user-device ([ORKO-19]) ===================================== - spent some time improving coverage for CI on standaline PoC - syncing with RedHat on virtio-sound [ORKO-19] <https://linaro.atlassian.net/browse/ORKO-19> [QEMU bits] <https://github.com/stsquad/qemu/tree/virtio/vhost-user-device> [vhost bits] <https://github.com/stsquad/vhost/tree/standalone/get-specs> [vhost-device bits] <https://github.com/stsquad/vhost-device/pull/new/standalone/vrng-experiment> Enable Arm Architecture in QEMU =============================== [slides] <https://www.bennee.com/~alex/presentations/kvm23-qemu-keynote.html> [live stream feed] <https://www.youtube.com/live/vy-3oYEDKCQ?feature=share&t=3531> QEMU Upstream Work ([UM-2]) =========================== - started collecting stray fixes, ran into issue with [plugin patch] - has a poor interaction with the SH4 gUSA sequence [UM-2] <https://linaro.atlassian.net/browse/UM-2> [plugin patch] <https://patchew.org/QEMU/CADc=-s5RwGViNTR-h5cq3np673W3RRFfhr4vCGJp0EoDUxvho…> Completed Reviews [1/1] ======================= [PATCH v3 0/3] Add VIRTIO sound card Message-Id: <cover.1689692765.git.manos.pitsidianakis(a)linaro.org> Absences ======== - Summer holidays until 2nd week of August Current Review Queue ==================== TODO [PATCH 0/4] chardev/char-fe: Document FEWatchFunc and use G_SOURCE_CONTINUE/REMOVE Message-Id: <20230705133139.54419-1-philmd(a)linaro.org> ============================================================================================================================================= TODO [PATCH v2 0/3] util/fifo8: Introduce fifo8_peek_buf() Message-Id: <20230705131859.53970-1-philmd(a)linaro.org> ================================================================================================================ TODO [PATCH v3 0/4] Virtio shared dma-buf Message-Id: <20230524091333.201767-1-aesteve(a)redhat.com> ================================================================================================= -- Alex Bennée Virtualisation Tech Lead @ Linaro

2 years, 9 months

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'(...)Applications/ClamAV/clamscan' is missing

by Andrzej Warzynski

Hi everyone, I'm not 100% sure whether this is a bot misconfiguration issue, but couldn't find any other source of this failure: ``` ******************** TEST 'test-suite :: MultiSource/Applications/ClamAV/clamscan.test' FAILED ******************** Executable '/home/tcwg-buildbot/worker/clang-aarch64-sve-vla/test/sandbox/build/MultiSource/Applications/ClamAV/clamscan' is missing ******************** ``` Link: https://lab.llvm.org/buildbot/#/builders/197/builds/8209 Would anyone be able to take a look? Thank you :) -Andrzej IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.

2 years, 9 months

3
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[ACTIVITY] report week ending 14 Jul

by Peter Maydell

Progress: * UM-2 [QEMU upstream maintainership] - investigated and fixed a bug in page-table-walk handling of debug accesses that was introduced by the FEAT_RME changes - that prompted me to look at a cleanup of some of the ptw code so that we consistently look at "which space is this walk for" and don't carry around a parallel boolean "secure/non-secure" that duplicates that information - found and fixed a few other ptw bugs along the way -- PMM

2 years, 10 months

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[ACTIVITY] week ending Jul. 9 2023

by Alex Bennée

Project Orko ============ - held kick-off with the EPAM guys [roadmap] <https://linaro.atlassian.net/wiki/spaces/ORKO/overview> Generic vhost-user-device ([ORKO-19]) ===================================== - PoC for standaline vhost-user daemons - [QEMU bits] - [vhost bits] - [vhost-device bits] [ORKO-19] <https://linaro.atlassian.net/browse/ORKO-19> [QEMU bits] <https://github.com/stsquad/qemu/tree/virtio/vhost-user-device> [vhost bits] <https://github.com/stsquad/vhost/tree/standalone/get-specs> [vhost-device bits] <https://github.com/stsquad/vhost-device/pull/new/standalone/vrng-experiment> Enable Arm Architecture in QEMU =============================== - Delivered talk at KVM Forum - See [slides] and [live stream feed] (dodgy audio) [slides] <https://www.bennee.com/~alex/presentations/kvm23-qemu-keynote.html> [live stream feed] <https://www.youtube.com/live/vy-3oYEDKCQ?feature=share&t=3531> QEMU Upstream Work ([UM-2]) =========================== - posted [PATCH 0/5] docs/devel: improve API documentation for QOM Message-Id: <20230619171437.357374-1-alex.bennee(a)linaro.org> - posted [PULL 00/38] maintainer updates for 8.1: testing, fuzz, plugins, docs, gdbstub Message-Id: <20230703134427.1389440-1-alex.bennee(a)linaro.org> [UM-2] <https://linaro.atlassian.net/browse/UM-2> Completed Reviews [4/4] ======================= [PATCH 0/2] tests: lcitool: Refresh to latest lcitool changes Message-Id: <cover.1685528076.git.eskultet(a)redhat.com> [PATCH v3 0/8] gdbstub: Add support for info proc mappings Message-Id: <20230606132743.1386003-1-iii(a)linux.ibm.com> [PATCH] contrib/plugins: add meson build file Message-Id: <20230615141315.961315-1-anton.kochkov(a)proton.me> [RFC v3 00/10] Native Library Calls Message-Id: <20230625212707.1078951-1-fufuyqqqqqq(a)gmail.com> Other ===== - various syncs Current Review Queue ==================== TODO [PATCH 0/4] chardev/char-fe: Document FEWatchFunc and use G_SOURCE_CONTINUE/REMOVE Message-Id: <20230705133139.54419-1-philmd(a)linaro.org> ============================================================================================================================================= TODO [PATCH v2 0/3] util/fifo8: Introduce fifo8_peek_buf() Message-Id: <20230705131859.53970-1-philmd(a)linaro.org> ================================================================================================================ TODO [PATCH v3 0/4] Virtio shared dma-buf Message-Id: <20230524091333.201767-1-aesteve(a)redhat.com> ================================================================================================= -- Alex Bennée Virtualisation Tech Lead @ Linaro

2 years, 10 months

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[ACTIVITY] Report for week #27

by Thiago Jung Bauermann

Hello, # TCWG CI - Changed tcwg_gnu-build.sh to apply GDB patch adding '--with-additional-debug-dirs' option, and ABE's gdb.conf to use it. Also changed both to add '--prefix /usr' option to GDB's configure. Both changes to fix ld.so debug info issues in GDB testsuite runs on armhf. - Testing changes to validate_failures.py and jenkins-scripts to handle empty gdb.sum. - Reviewed a few Gerrit requests. -- Thiago

2 years, 10 months

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[ACTIVITY] report week ending 6 Jul

by Peter Maydell

Progress (short week, 3 days): * UM-2 [QEMU upstream maintainership] - softfreeze is next week, so spent some time putting together a pull request, fixing the bugs which the CI tests found in it, etc * QEMU-422 [QEMU Arm Neoverse V1 vCPU for TCG] - now that we implement all the necessary features (excluding some trace/profiling type stuff that is out-of-scope for QEMU, and also FEAT_NV that we might come back to later), sent out the patchset to define a 'neoverse-v1' CPU type for QEMU -- PMM

2 years, 10 months

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[ACTIVITY] Report for week #26

by Thiago Jung Bauermann

Hello, # TCWG Infrastructure - Investigated why the CI didn't recover from empty gdb.sum, since it was supposed to. - Fixing validate_failures.py and tcwg_gnu-build.sh to correctly handle empty gdb.sum. - Fixing GDB armhf CI jobs to find distro's debug info. # CI Babysitting - Verified that a couple of regressions I reported last week were fixed in trunk. -- Thiago

2 years, 10 months

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[ACTIVITY] Report for week #25

by Thiago Jung Bauermann

Hello, # TCWG CI — GDB - Investigated why the GDB check jobs stopped succeeding, as reported by Maxim. It turns there was an upstream commit (which was soon reverted) that broke generation of the gdb.sum file and consequently our baseline results became empty. Theoretically the CI should recover from that but we don't deal well with this corner case. With Maxim's help, restored the baseline and now things should be back to normal. Will improve our scripts to avoid this trap. # CI Babysitting This week was my turn to baby sit the CI. - Investigated 12 regressions in GCC and reported 3. The others were already fixed. - Investigated 1 regression in GDB but it wasn't actually one. - Investigated 1 regression in QEMU but it was already fixed. -- Thiago

2 years, 10 months

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[ACTIVITY] report week ending 23 Jun (inc. KVM Forum trip report)

by Peter Maydell

Progress: * UM-2 [QEMU upstream maintainership] - catch up on email after a week away - Put together some arm pull requests - sent out draft QEMU summit minutes for review - sent patch to avoid using the buggy __builtin_subcll in Apple Clang 14 - sent patch fixing build error with newer xkeyboard-data - some gardening of Coverity issue reports Last week was KVM Forum in Brno -- here's a quick trip summary: This year KVM Forum was a slightly smaller conference (2 days, single-track), as we are now organizing it independently of the Linux Foundation. The independent organization went pretty well this year (despite the slightly awkward short notice) and the conference was very useful both for the talks and for the hallway track. Interesting talks (just a sampling biased to my interests): * KVM: Arm Confidential Compute Architecture Support Suzuki Poulose presented a summary of FEAT_RME and the CCA hardware and software architecture, and how it's intended to fit into KVM * KVM/arm64: Episode V - The Blob Strikes Back Immediately following was Marc Zyngier and Oliver Upton from Google: their talk was a pretty strong critique of the CCA software stack architecture. Their central point is that having the RMM be "part of the firmware" rather than "part of the hypervisor" is going to cause a rerun of all the issues we've seen with dubious and non-upgradable vendor code in EL3. Secondly, having the fixed API between the hypervisor and the RMM restricts to least-common-denominator and provides no room for experimentation and optimizations. They want an architected way to deploy an RMM at boot time. * Handling complex guest exits with eBPF Will Deacon presented what he described as "conference driven development" -- an interesting prototype of having device models in the host kernel that are implemented in eBPF. This (in theory) gives you the performance gains of an in-kernel device without it putting a lot of C code onto the security boundary between the guest and host. * Challenges Revisited in Supporting Virt CPU Hotplug on architectures that don't Support CPU Hotplug (like ARM64) James Morse (Arm) and Salil Mehta (Huawei) presented on CPU hotplug. The underlying problem here remains that Arm has no hardware hotplug handling, so there's no clear model for what hotplug on a VM should look like. Cloud vendors have an obvious desire for the x86-style tooling to Just Work on Arm too. The gap between "we have a prototype that seems to work" and "upstreamable maintainable code" has not yet been bridged, though... * QEMU Arm CPU models and KVM Cornelia Huck (RedHat) had a talk that was intended as a statement of the problem rather than a proposed solution. At the moment we only let a KVM guest see the same CPU type as the host and don't have a mechanism for presenting a subset of features to it. KVM is about to get support for letting the VMM define what the guest should see in the ID registers, but how should we expose that to QEMU users without ending up with a thousand command line sub-options to turn on and off every architectural FEAT_FOO? And how do we deal with errata workarounds, which the guest currently selects based on the MIDR value? As usual, we held the QEMU Summit (an hour-long maintainer discussion mostly about process and organizational issues) during KVM Forum. I still need to write up the minutes for this, but they'll be published on the qemu-devel list shortly. thanks -- PMM

2 years, 10 months

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Need emit_expr to write right shifted value.

by zac.walker＠linaro.org

Hi, In binutils I need to write an offset between two symbols shifted right by 2 bits. This offset is written to the xdata section. My code currently looks like this: exp.X_op = O_subtract; exp.X_add_symbol = symbol1; exp.X_op_symbol = symbol2; emit_expr (&exp, 2); This works fine but obviously the result value is not shifted. Anyone have a good option is to shift the output of emit_expr at write time? I cannot use resolve_expression because the symbols do not have correct addresses at the time this code executes. Any help appreciated, Zac

2 years, 10 months

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[ACTIVITY] Report for week #24

by Thiago Jung Bauermann

Hello, # TCWG CI — GDB - Changed tcwg_gnu-build.sh to apply GDB testsuite patch to avoid infinite loop in tcwg_gdb_check--master-arm jobs, while it isn't committed upstream. - Started investigating corrupt gdb.sum.1 file in tcwg_gdb_check--master-arm jobs. I can't reproduce it by manually running the CI's "make check-gdb" command line, nor by using ABE. I can reproduce it with tcwg_gnu-build.sh though. - Came up with validate_failures.py change to make it cope with the corrupt gdb.sum.1 file, while the underlying cause isn't known. Submitted the change upstream. # TCWG Infrastructure - Reviewed some Gerrit requests for our CI scripts. # Misc - Did some travel planning for Linaro Employee Meeting and GNU Tools Cauldron. -- Thiago

2 years, 10 months

1
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2026

2025

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