Upstream Work ([VIRT-109])
==========================
- reviewed {Qemu-devel} {PATCH for-4.0 v2 00/37} tcg: Assorted
cleanups Message-Id:
<20181123144558.5048-1-richard.henderson(a)linaro.org>
- looked at common part of {Qemu-devel} {PATCH 2 00/39} Windbg
supporting Message-Id:
<154401431697.8440.845616703562380651.stgit(a)Misha-PC.lan02.inno>
- finished review of {PATCH v6 00/13} hardfloat Message-Id:
<20181124235553.17371-1-cota(a)braap.org>
- 2-3x speed-ups for FPU heavy workloads!
- finished prototype of [enabling tcg system tests]
- includes some more userspace tests as well
- just missed posting RFC, will post next week
[VIRT-109] https://projects.linaro.org/browse/VIRT-109
[enabling tcg system tests]
https://github.com/stsquad/qemu/tree/testing/enable-system-tcg-tests-v1
Other Tasks
===========
- debugged compiler failures on SynQuacer
- turned out it was dodgy RAM *slot layout* - system now stable
again
- did some bug triage/tagging in QEMU bug database
- update JIRA tickets as per QEMU initiative thread Message-Id:
<87wop4gezg.fsf(a)linaro.org> :todo
Completed Reviews [3/3]
=======================
{PATCH v3 00/16} tcg: Assorted cleanups
Message-Id: <20181130215221.20554-1-richard.henderson(a)linaro.org>
- CLOSING NOTE [2018-12-03 Mon 10:46]
Easier review with the re-org of removal and clean-up patches
{Qemu-devel} {PATCH for-4.0 v2 00/37} tcg: Assorted cleanups
Message-Id: <20181123144558.5048-1-richard.henderson(a)linaro.org>
- CLOSING NOTE [2018-12-03 Mon 10:47]
Got part way through, subset reposted and reviewed. Some questions
remain on the efficiency of ool softmmu w.r.t various
micro-architectures.
{PATCH v6 00/13} hardfloat
Message-Id: <20181124235553.17371-1-cota(a)braap.org>
- CLOSING NOTE [2018-12-05 Wed 12:48]
Looking good. I've proposed myself as another maintainer for FPU
emulation and will handle the pull request once the tree opens.
Absences
========
- Christmas Holidays
- Connect BKK19 (1-5th April 2019)
Current Review Queue
====================
* {RFC} arm: Allow system registers for KVM guests to be changed by QEMU code
Message-Id: <20181206151401.13455-1-peter.maydell(a)linaro.org>
* {Qemu-arm} {PATCH 00/13} Support disabling TCG on ARM
Message-Id: <20181113165247.4806-1-sameo(a)linux.intel.com>
* {PATCH for-4.0 0/5} tcg/i386: Improve guest_base handling
Message-Id: <20181203160840.15115-1-richard.henderson(a)linaro.org>
* {Qemu-devel} {PATCH for-4.0 00/71} qtest: qgraph driver framework
Message-Id: <1543851204-41186-1-git-send-email-pbonzini(a)redhat.com>
* {Qemu-arm} {PATCH v7 00/16} gdbstub: support for the multiprocess extension
Message-Id: <20181123091729.29921-1-luc.michel(a)greensocs.com>
* {PATCH 0/7} Acceptance Tests: basic architecture support
Message-Id: <20181004151429.7232-1-crosa(a)redhat.com>
--
Alex Bennée
[LLVM-499] LLD support for linking the linux kernel
- [LLVM-504] Support for linker script symbol assignment to an alias.
-- Diagnosed problem and made reproducer on PR.
-- Reviewed the upstream patch.
- [LLVM-503] Support for discarding .dynamic, .dynstr and .dynsym
-- Reviewed upstream patch and proposed testcase that is
representative of the kernel use case.
Some revisiting of scripts and advice on how to cross compile clang
libraries. Looks like I have some updates to do to the documentation
for some configurations I haven't tried before.
- 2 days at ARM internal Codegen conference. Really good event,
standard of work was very high, left enthused.
Planned absences:
Christmas Holiday from 17th December to 4th January
== Progress ==
* FDPIC
- GCC: no feedback yet on v4 patches
- GDB: did not decide yet how/if to commonalize with frv code. Asked
for advise on the gdb list.
* GCC upstream validation:
- reported a few regressions, helped testing some patches
- dealing with some random results, still
- trying qemu-3.1.0-rc3, memory consumption problems with
aarch64-linux. LSF reports (cgroup-based) do not seem consistent with
time --verbose.
* GCC:
- rebased ubsan / bare-metal patches. Trying to build an LLVM
toolchain to see how to properly apply my patches
* misc (conf-calls, meetings, emails, ....)
- reviewing/submitted infra script patches
- ran Spec2006 on aarch32 using gcc-8.2 sysroot, results match the
previous ones, so the improvements are only imputable to the compiler.
- dealing with nasty ST-internal infrastructure problems
- trying to look at noinit/persistent attributes provided by other
toolchains, need a windows machine :(
== Next ==
FDPIC:
- GCC: handle feedback on v4 patches
- GDB: update patches
- uclibc-ng: look at how to test fdpic mode with openadk
Benchmarks:
- collect results
Validation:
- isolate if/why qemu-3.1.0-rc3 consumes more memory than 2.11 for
aarch64-linux target
Progress:
* VIRT-65 [QEMU upstream maintainership]
- release work (we needed an rc4, and then an rc5 due to a
late-breaking security bug)
- wrote a patch which I hope will fix synchronization of system
register state to KVM for a case where QEMU code wants to change
the register values, which it does when QEMU is arranging to inject
an exception into the guest
- catching up on patch review and assembling target-arm.next
ready for when the tree reopens
- some simple patches fixing minor memory leaks spotted by clang LeakSanitizer
- sent a patch for a race condition that meant we would sometimes ignore
a guest-requested system reset or otherwise get confused by it
thanks
-- PMM
== Progress ==
# [LLVM-492] [Thumb GlobalISel] Lower parameters for Thumb functions
- Committed upstream
# [LLVM-500] [Thumb GlobalISel] Support G_ADD, G_SUB, G_MUL
- Started working on this but it became apparent that the existing
tests would be easier to reuse if we had support for G_LOAD first
# [LLVM-506] [Thumb GlobalISel] Support G_LOAD and G_STORE
- Investigated whether we could get TableGen to select G_LOADs and
G_STOREs by porting ComplexPattern
- Unfortunately that is not enough, and even AArch64 has
hand-written code for it in the instruction selector
- Will handle it the ugly way next week
== Plan ==
# LLVM-506, LLVM-500
Greetings,
I’m trying to have the Aarch64 gcc optimize a single function using the O3 optimization in this manner:
void __attribute__ ((optimize ("-O3", "-ftree-vectorize" )))
However, when examining the assembler code, there is no trace of any optimization beyond the project default.
The only way to successfully enforce the optimization is using -O3 in the gcc command line. Then the compiler produces ARM neon instructions.
Do you know any issues regarding function level optimizations and the Aarch64 gcc?
Regards
[Upstream]
Posted a patch set aimed at register allocation vs function calls. It does
reduce code size by a percent or two. Emilio did some benchmarking and found
that it does help a bit, but does not completely eliminate the effect of the
call+ret overhead on the most modern of x86 implementations.
Reviewed v2 of tcg/riscv. Still a lot of work to be done, I think.
Cleanup of all tcg backends vs re-translation, which is no longer a thing.
Cleanup of tcg/i386 vs scratch registers.
[Other]
Updated the mustang to ubuntu 18.10. I was seeing some weirdness
that I'm hoping I can blame on the bionic 4.15 kernel and will be
gone with the cosmic 4.18 kernel. Fingers crossed...
r~
o 4 days week.
o LLVM
* 7.0.1-rc2:
- Miscompare on AArch64:
No luck with Sanitizers enabled, still digging.
* Machine Outliner on ARM prototype:
- Fixed Pic code issue.
- llvm bootstrap in thumb mode gives 4% code size reduction.
- Investigating new issues
o Misc
* Various meetings and discussions.
=== Work done during the past 2 weeks ===
* GNU-296 (Fix stack protector on ARM): committed!
* LLVM-432 (Support arithmetic on FileCheck regex variable):
+ finished reworking parsing code to be separate from evaluation and support
more complex expression
+ fix compile errors and bugs found when running tests added to check feature
* Write patch to diagnose error when compiling Armv8-M Baseline CMSE
code with -mfpu
-> as unintended consequence, needs rewrite
* Wrote and committed patch to improve comments for some data structure in ld
* Misc:
+ various meeting about my departure from Arm & Linaro
=== Plan for week 49 ===
LLVM-432 (Support arithmetic on FileCheck regex variable):
+ extend testcase coverage (add tests for latest syntax change and
add more negative testing)
+ clean up the code
+ improve documentation
* Try to reproduce perf issue mentioned in week #30's weekly report on
latest perf
* Line management:
+ continue progress on rotations
== Progress ==
* FDPIC
- GCC: no feedback yet on v4 patches
- GDB: started looking at the patches, some parts are very similar to
FRV, maybe worth commonalization.
* GCC upstream validation:
- reported a few regressions, helped testing some patches
- dealing with some random results, still
- trying qemu-3.1.0-rc1, memory consumption problems with
aarch64-linux. Could not properly test cortex-m0 support yet, because
building gcc --with-cpu=cortex-m0 currently fails.
* GCC:
- bug report on aarch64 about misaligned accesses. I do not have
access to LHG gerrit, Maxim will look at isolating the problem.
- rebased ubsan / bare-metal patches. Really need to look at how to
merge them into LLVM
* misc (conf-calls, meetings, emails, ....)
- reviewing infra script patches
- ran Spec2006 on aarch64 using gcc-8.2 sysroot, results match the
previous ones, so the improvements are only imputable to the compiler.
Started the same experiment on aarch32
- some Jira/goals discussions
- dealing with nasty ST-internal infrastructure problems
== Next ==
FDPIC:
- GCC: handle feedback on v4 patches
- GDB: update patches
- uclibc-ng: look at how to test fdpic mode with openadk
Benchmarks:
- collect results
Validation:
- isolate why qemu-3.1.0-rc1 consumes much more memory for aarch64-linux target
Progress:
* VIRT-65 [QEMU upstream maintainership]
- release work (it is looking like we'll need an rc4 next week)
- worked out some patches which hopefully will fix running
QEMU on OSX Mojave (testing still required)
- code review
- sent a cleanup patchset that removes the load_image()
function (which is not possible to use safely and which we
marked as deprecated way back in 2008!)
* VIRT-268 [QEMU support for dual-core Cortex-M Musca board]
- implemented test case which demonstrates that we incorrectly share
translated code between heterogenous CPUs and behave wrongly as a
result (using the existing xlnx-zcu102 board)
thanks
-- PMM
[LLVM-493] LLD link failure on KASLR for AArch64 Linux kernel
The linux kernel can build in an ASLR mode that is currently causing LLD
some problems. There are a few oddities in the kernel that aren't quite
right but there are some problems in LLD that need resolving as well. has
been a couple of interesting days trying to work out why some strange
options have been used.
[LLVM-484] LLD combination of dynamic relocs into a single section
Committed upstream
[LLVM-486] Error if user code defines _GLOBAL_OFFSET_TABLE_
Committed upstream
[LLVM-489] Measure (cross) linking of performance of LLD on Chrome
Performance of linking AArch64 matches X86, roughly twice as fast as
ld.gold and five times faster than ld.bfd.
[TCWG-1492] Investigated why git-clone and git-fetch might hang/deadlock.
Back up might be to put a timeout/retry.
[Other]
Submitted LLVM team goals for the TCWG team
Wrote up how TCWG use Jenkins and CI, now in Confluence.
Planned Absences:
ARM internal Compiler conference 4th/5th December
Christmas holiday 17th December - 4th January
QEMU Tooling ([VIRT-252])
=========================
QEMU plugin support ([VIRT-280])
- reviewed Emilio's {RFC 00/48} Plugin support Message-Id:
<20181025172057.20414-1-cota(a)braap.org>
- looks like a good basis for going forward if we can work out the
kinks
- port my example tools to his framework :todo
[VIRT-280] https://projects.linaro.org/browse/VIRT-280
Upstream Work ([VIRT-109])
==========================
- did a quick pass at [enabling system tests in check-tcg]
- started reviewing {Qemu-devel} {PATCH for-4.0 v2 00/37} tcg:
Assorted cleanups Message-Id:
<20181123144558.5048-1-richard.henderson(a)linaro.org>
[VIRT-109] https://projects.linaro.org/browse/VIRT-109
[enabling system tests in check-tcg]
https://github.com/stsquad/qemu/tree/tests/enable-system-tests
Testing and CI
==============
[VIRT-2] https://projects.linaro.org/browse/VIRT-2
KVM CI Loop ([VIRT-2])
- The [LKFT team] are working with gregkh to ensure -stable is tested
for KVM regressions
- wrote up the State of testing for KVM Message-Id:
<874lc14194.fsf(a)linaro.org>
- look at example regression to see what would have caught the failure
:todo
- look at kselftest and understand it's place :todo
[VIRT-2] https://projects.linaro.org/browse/VIRT-2
[LKFT team] https://lkft.linaro.org/
Other Tasks
===========
- need to concluded actions from The QEMU initiative thread
Message-Id: <87wop4gezg.fsf(a)linaro.org> :todo
Completed Reviews [2/2]
=======================
{RFC 00/48} Plugin support
Message-Id: <20181025172057.20414-1-cota(a)braap.org>
- CLOSING NOTE [2018-11-28 Wed 14:13]
Hashed out a number of things. Emilio will look at a single-pass
option and it makes things easier or not. It was also suggested we
could move instruction fetch to helpers outside of the individual
front-ends to keep the plugin call points in the core translator and
avoid having to tweak each front-end for support. A number of
pre-requisites were discussed including some de-macrofication work
to make the code easier to follow and instrument.
{PATCH 0/4} xxhash patches for 4.0
Message-Id: <20181123230206.12629-1-cota(a)braap.org>
- CLOSING NOTE [2018-11-28 Wed 15:09]
Clean-up to xxhash to match original and handle expanded hashes
Absences
========
- Christmas Holidays
- Connect BKK19 (1-5th April 2019)
Current Review Queue
====================
* {Qemu-devel} {PATCH for-4.0 v2 00/37} tcg: Assorted cleanups
Message-Id: <20181123144558.5048-1-richard.henderson(a)linaro.org>
* {PATCH v6 00/13} hardfloat
Message-Id: <20181124235553.17371-1-cota(a)braap.org>
* {Qemu-arm} {PATCH v7 00/16} gdbstub: support for the multiprocess extension
Message-Id: <20181123091729.29921-1-luc.michel(a)greensocs.com>
* {Qemu-arm} {PATCH 00/13} Support disabling TCG on ARM
Message-Id: <20181113165247.4806-1-sameo(a)linux.intel.com>
* {PATCH 0/7} Acceptance Tests: basic architecture support
Message-Id: <20181004151429.7232-1-crosa(a)redhat.com>
* {PATCH v7 00/19} Fixing record/replay and adding reverse debugging
Message-Id: <20181010133333.24538.53169.stgit@pasha-VirtualBox>
--
Alex Bennée
o 4 days week.
o LLVM
* 7.0.1-rc2:
- Miscompare on AArch64 is related to host compiler, still digging.
* Machine Outliner on ARM prototype:
- IR Outliner experiments:
Commented upstream, and reducing problematic test case.
o Misc
* Various meetings and discussions.
Four day week (Happy Thanksgiving, all you Europeans)
[Upstream]
Posted patches making bswap during qemu_ld/st optional. The prompt was
reviewing the tcg/riscv/ patch set, but I've wanted to do this for ages.
This should avoid the need for reservation of scratch registers on some hosts
that can ill afford it -- in particular i386 and aa32.
In the process I ran into two other places that x86 used those scratch
registers: stores from non-q-registers and bsd-user.
I included patches for both of those (freebsd only; net/openbsd will work so
long as guest_base == 0 and will abort at runtime otherwise).
I still need to audit the other hosts before dropping the call-clobbering from
user-only within tcg.c.
r~
== Progress ==
* FDPIC
- Cortex-M uClibc-ng patch merged
- GCC: no feedback yet on v4 patches
* GCC upstream validation:
- reported a few regressions
- dealing with some random results, again
- trying qemu-3.1.0-rc1, maybe some memory consumption problems, tbc
* GCC:
- bug report on aarch64 about misaligned accesses. I do not have
access to LHG gerrit, Maxim will look at isolating the problem.
- rebased ubsan / bare-metal patches. Really need to look at how to
merge them into LLVM
* misc (conf-calls, meetings, emails, ....)
- reviewing infra script patches
- ran Spec2006 using gcc-8.2 sysroot, to avoid differences caused by
glibc versions. Fortran benchmarks could not run when compiled with
gcc-5/gcc-6 because libgfortran changed .so version compared to gcc-8.
== Next ==
FDPIC:
- GCC: handle feedback on v4 patches
- uclibc-ng: look at how to test fdpic mode with openadk
Benchmarks:
- collect results
Validation:
- check if qemu-3.1.0-rc1 is OK for my GCC validations
[LLVM-486] Error id user defines _GLOBAL_OFFSET_TABLE_ (upstream review)
[LLVM-484] Fix linker script dynamic relocations combination into a single
output section (upstream review)
[LLVM-483] cortex-a53 erratum fix interaction with TLS relaxation (upstream
review)
[LLVM-489] Measure (cross) linking performance of LLD for AArch64 and Arm.
Looking for large projects that I can build for Arm and AArch64
- Firefox seems to have some ARM Android cross build support but it does
not appear to be working too well.
- Chrome can cross build to ARM and AArch64 Android. Have been able to
build AArch64 so far.
Notably both projects don't support building natively on AArch64, there are
quite a few build dependencies for which only x86 support is available.
Raised Jira tickets for recent PRs fixed
2019 Planning
- Drafted objectives document for LLVM team
- Drafted some Jira suggestions for TCWG
QEMU Tooling ([VIRT-252])
=========================
[VIRT-252] https://projects.linaro.org/browse/VIRT-252
QEMU plugin support ([VIRT-280])
- continued reviewing Emilio's {RFC 00/48} Plugin support Message-Id:
<20181025172057.20414-1-cota(a)braap.org>
- port my example tools to his framework :todo
[VIRT-280] https://projects.linaro.org/browse/VIRT-280
Upstream Work ([VIRT-109])
==========================
- finished reviewing {RFC PATCH v2 00/23} KVM: arm64: Initial support
for SVE guests Message-Id:
<1538141967-15375-1-git-send-email-Dave.Martin(a)arm.com>
[VIRT-109] https://projects.linaro.org/browse/VIRT-109
Other Tasks
===========
- started The QEMU initiative thread Message-Id:
<87wop4gezg.fsf(a)linaro.org> for JIRA discussion
Completed Reviews [3/3]
=======================
{RFC PATCH v2 00/23} KVM: arm64: Initial support for SVE guests
Message-Id: <1538141967-15375-1-git-send-email-Dave.Martin(a)arm.com>
- CLOSING NOTE [2018-11-22 Thu 15:36]
My only major concern is if the query API is too gold plated.
{RFC PATCH 0/2} docker: Add gentoo-mipsr5900el-cross image
Message-Id: <20181118203312.5376-1-f4bug(a)amsat.org>
{PATCH} docker: dockerfile for openSUSE Leap
Message-Id: <87k1lai2vo.fsf(a)linaro.org>
Absences
========
- Christmas Holidays
- Connect BKK19 (1-5th April 2019)
Current Review Queue
====================
* {RFC 00/48} Plugin support
Message-Id: <20181025172057.20414-1-cota(a)braap.org>
* {Qemu-devel} {PATCH for-4.0 v2 00/37} tcg: Assorted cleanups
Message-Id: <20181123144558.5048-1-richard.henderson(a)linaro.org>
* {Qemu-arm} {PATCH v5 00/16} gdbstub: support for the multiprocess extension
Message-Id: <20181110081147.4027-1-luc.michel(a)greensocs.com>
* {Qemu-arm} {PATCH 00/13} Support disabling TCG on ARM
Message-Id: <20181113165247.4806-1-sameo(a)linux.intel.com>
* {PATCH 0/7} Acceptance Tests: basic architecture support
Message-Id: <20181004151429.7232-1-crosa(a)redhat.com>
* {PATCH v7 00/19} Fixing record/replay and adding reverse debugging
Message-Id: <20181010133333.24538.53169.stgit@pasha-VirtualBox>
--
Alex Bennée
Progress:
* VIRT-65 [QEMU upstream maintainership]
- release work
- code review
- sent patch fixing Coverity issue in Xen PCI device passthrough
(this was our last outstanding issue with no patch on the list!)
* VIRT-268 [QEMU support for dual-core Cortex-M Musca board]
- some initial investigation of what changes are going to be needed
for heterogenous-cpu support in QEMU
- started on a test case using the existing xnlx-zcu102 board (which
has a heterogenous config that works only by accident)
thanks
-- PMM
== Progress ==
# Monday off
# [LLVM-479] Check current status of GlobalISel
- Looked into new patterns that can be selected by TableGen and
forked LLVM-481 and LLVM-482 out of that
- Ran a test-suite and a selfhost with GlobalISel and had a look at
the fallbacks
# [LLVM-481] [ARM GlobalISel] Test BFC
- Committed upstream
# [LLVM-482] [ARM GlobalISel] Enable CLZ
- Most of the work is done, ready to commit next week
== Plan ==
Wrap up LLVM-482 and LLVM-479
Fork more stories out of LLVM-479
The Linaro Toolchain Working Group (TCWG) is pleased to announce the
2018.11 snapshot of Linaro GCC 6 source package.
o This Linaro GCC 6 snapshot[1] is based on FSF GCC 6.5+svn265890 and
includes performance improvements and bug fixes backported from
mainline GCC. This snapshot will be part of the final maintenance release,
as the upstream GCC 6 branch is at the end of its maintenance lifespan.
This snapshot tarball is available on:
http://snapshots.linaro.org/components/toolchain/gcc-linaro/6.5-2018.11/
Interesting changes in this GCC source package snapshot include:
* Updates to GCC 6.4+svn265890
o Subscribe to the important Linaro mailing lists and join our IRC channels to
stay on top of Linaro development.
** Linaro Toolchain Development "mailing list":
http://lists.linaro.org/mailman/listinfo/linaro-toolchain
** Linaro Toolchain IRC channel on irc.freenode.net at @#linaro-tcwg@
* Bug reports should be filed in Bugzilla against GCC product:
http://bugs.linaro.org/enter_bug.cgi?product=GCC
* Interested in commercial support? inquire at "Linaro support":
mailto:support@linaro.org
[1]. Source package snapshots are defined when the compiler is only
put through unit-testing and full validation is not performed.
Mark Murray Staff Software Engineer | Arm
. . . . . . . . . . . . . . . . . . . . . . . . . . .
p: +44 1223 405082
arm.com <http://www.arm.com>
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.
o 4 days week.
o LLVM
* 7.0.1-rc2:
- Uploaded ARM and AArch64 binaries
- Investigating miscompare on AArch64
* Machine Outliner on ARM prototype:
- IR Outliner experiment gave interesting code size reduction
o Misc
* Various meetings and discussions.
* CI patch reviews
Three day week.
[GNU-180 # Fix gcov crash on program exit]
Fiddled around with TI-RTOS for a while before I realized that was sort of
beside the point. Gave the reporter a method do avoid dumping during the
global destructors. Still need to look into where the reported stack space
problem might be.
[Upstream]
Out-of-line softmmu patches got some work. Added ppc64 support. Fixed a race
and a code removal crash. Emilio verified -5% aa64 boot+shutdown time, but it
performed less well on spec2006.
Reviewed risc-v host patch set.
r~
QEMU Tooling ([VIRT-252])
=========================
QEMU plugin support ([VIRT-280])
- started reviewing Emilio's {RFC 00/48} Plugin support Message-Id:
<20181025172057.20414-1-cota(a)braap.org>
- port my example tools to his framework :todo
[VIRT-280] https://projects.linaro.org/browse/VIRT-280
Upstream Work ([VIRT-109])
==========================
- started looking at {RFC PATCH v2 00/23} KVM: arm64: Initial support
for SVE guests Message-Id:
<1538141967-15375-1-git-send-email-Dave.Martin(a)arm.com>
[VIRT-109] https://projects.linaro.org/browse/VIRT-109
Other Tasks
===========
- [Video for KVM Forum QEMU status report] is up
- the rest of the [sessions are here]
- posted {PULL for 3.1 0/2} Testing tweaks Message-Id:
<20181114131008.27599-1-alex.bennee(a)linaro.org>
[Video for KVM Forum QEMU status report]
https://www.youtube.com/watch?v=GZBd3jt5iA8
[sessions are here]
https://www.youtube.com/channel/UCRCSQmAOh7yzgheq-emy1xA/videos
Completed Reviews [3/3]
=======================
{PATCH} tests/tcg/multiarch: fix 32bit linux-test on 64bit host
Message-Id: <20181113175437.26492-1-laurent(a)vivier.eu>
{Qemu-devel} {PATCH} hax: Support for Linux hosts
Message-Id: <20181114130428.32326-1-asanchez(a)kryptoslogic.com>
{Qemu-devel} {PATCH} target: hax: replace g_malloc with g_malloc0
Message-Id: <1542261954-4060-1-git-send-email-liq3ea(a)gmail.com>
Absences
========
- Christmas Holidays
- Connect BKK19 (1-5th April 2019)
Current Review Queue
====================
* {RFC PATCH v2 00/23} KVM: arm64: Initial support for SVE guests
Message-Id: <1538141967-15375-1-git-send-email-Dave.Martin(a)arm.com>
* {Qemu-arm} {PATCH v5 0/4} target/arm: KVM vs ARMISARegisters
Message-Id: <20181113180154.17903-1-richard.henderson(a)linaro.org>
* {Qemu-devel} {PATCH for-4.0 00/17} tcg: Move softmmu out-of-line
Message-Id: <20181112214503.22941-1-richard.henderson(a)linaro.org>
* {Qemu-arm} {PATCH 00/13} Support disabling TCG on ARM
Message-Id: <20181113165247.4806-1-sameo(a)linux.intel.com>
* {Qemu-devel} {PATCH for-4.0 00/17} tcg: Move softmmu out-of-line
Message-Id: <20181112214503.22941-1-richard.henderson(a)linaro.org>
* {Qemu-arm} {PATCH v5 00/16} gdbstub: support for the multiprocess extension
Message-Id: <20181110081147.4027-1-luc.michel(a)greensocs.com>
--
Alex Bennée
LLD bug fixing and triage
pr39678 Calculation of DT_PLTRELSZ with strange linker script.
pr39662 Request to add more emulations
pr39634 LTO and references from inline symbols
D54474 Fix for incorrect relocation span out of ifunc review
D54624 Redefinition of _GLOBAL_OFFSET_TABLE_
=== Work done during the past 2 weeks ===
* Resurrect code size optimization for fmul/dmul from Tony Wang: bootstraping
+ rework slightly to better deal with switch of section and deal with
several possible section layout
+ start anew with a new approach based on symbol visibility
-> works without -gc-sections and does not rely on section layout
* Fix -mslow-flash-data: ready to upstream on Monday
+ some more cleanup and code improvement
* LLVM-432 (Support arithmetic on FileCheck regex variable):
+ started reworking parsing code to be separate from evaluation and support
more complex expression
* Infrastructure code review
=== Plan for week 47 ===
* LLVM-432 (Support arithmetic on FileCheck regex variable):
+ extend testcase coverage (add tests for latest syntax change and
add more negative testing)
+ finish cleaning up the code
* Try to reproduce perf issue mentioned in week #30's weekly report on
latest perf
* Line management.
Progress:
* VIRT-251 [AArch32 Hyp/running microvisors]
- fixes to the issues running L4Re/Fiasco have now been committed
to QEMU master for the 3.1 release
- some minor remaining missing functionality not needed for these guests
has been recorded as subtasks of VIRT-65
- this Epic is now closed!
* VIRT-65 [QEMU upstream maintainership]
- release work
- looked again at automation of uploads to the Coverity Scan service
(last try was last year); sent out revised patchset
- code review:
+ "sbsa reference board" model
+ LOR, HPD, AA32HPD extension support (rth)
+ Minimize TLB flushing for ASID changes (rth)
+ Support for loading uboot "noload" uimage files
+ better PMUv3 emulation
+ micro:bit SoC device models
thanks
-- PMM
== Progress ==
* FDPIC
- Cortex-M uClibc-ng patch still pending
- GCC: updated patches and sent v4
Tried to isolate the regressions observed on xtensa uclinux
toolchain with my patches.
Built a qemu-system-arm -based platform to run tests involving the
kernel. Built and ran a few LTP tests.
Unfortunately, LTP has dropped/is dropping support for uclinux
configs, for lack of interest
* GCC upstream validation:
- reported a few regressions
- dealing with some random results, again
* GCC:
- bug report on aarch64 about misaligned accesses. Waiting for more
details to reproduce the problem.
* misc (conf-calls, meetings, emails, ....)
- reviewing infra script patches
== Next ==
FDPIC:
- GCC: handle feedback on v4 patches
- uclibc-ng: look at how to test fdpic mode with openadk
== Progress ==
* Catch up on things
- Remind myself what a laptop looks like, install updates etc etc
- Figure out new links, machines etc
- Clean up inbox
* [LLVM-59] Small changes to the LLVM helper scripts
- Had a look at all the remaining issues and closed them as obsolete
or already implemented
* [LLVM-479] Check current status of GlobalISel
- Read the mailing list to see what I’ve missed
- Started looking at the code
- Trying to run the test-suite on a TK1
* Misc
- Fixed a simple buildbot breakage
- Meetings
== Plans ==
* LLVM-479
== This Week ==
* GNU-405: Implement division using vrecpe/vrecps (1/10)
- Committed patch
* SVE ACLE (2/10)
- Continue work on shift intrinsics
* PR83750 (1/10)
- Addressing upstream comments
* Holidays (6/10)
- Diwali festival
== Next Week ==
- Continue working on SVE ACLE and PR83750
o 4 days week.
o LLVM
* 7.0.1-rc2:
- Built ARM and AArch64 binaries
- Investigating miscompare on AArch64
* Machine Outliner on ARM prototype:
- Investigating issues in PIC mode
- Testing IR Outliner
o Misc
* Various meetings and discussions.
[VIRT-241 # QEMU ARMv8.x support ]
The new ARM ARM was released (DDI0487 D_a) including ARMv8.4.
Add jira cards for all of the v8.4 features. Rearrange all of
the stories into a hierarchy so that it's easier to track which
cards belong to which architecture revision.
[VIRT-263 # ARMv8.1-VHE Virtual Host Extensions ]
Working my way through this rather large extension:
* Cleanup (most) direct uses of hcr_el2.
* Add new hypervisor virtual timer.
* Add contextidr_el2 and use it in breakpoint matching.
* Add system register aliasing and redirection.
* Added a new mmu_idx for the NS EL2&0 regime;
working through all the places that should be handled.
[Upstream]
Posted kvm-vs-idregs patch set v3.
r~
== Progress ==
* FDPIC
- Cortex-M uClibc-ng patch still pending
- GCC: handling feedback on v3 patches.
Managed to build/check xtensa uclinux toolchain with my patches.
Largely better, but a few new failures.
- working on kernel + qemu-system env to run more tests. Got help from
Nicolas Pitre.
* GCC upstream validation:
- reported a few regressions
- dealing with some random results, again
* GCC:
- bug report on aarch64 about misaligned accesses. Waiting for more
details to reproduce the problem.
* misc (conf-calls, meetings, emails, ....)
- reviewing infra script patches
== Next ==
FDPIC:
- GCC: followup v3 patches
- uclibc-ng: look at how to test fdpic mode with openadk
- use qemu-system mode to run more tests
Progress:
* VIRT-65 [QEMU upstream maintainership]
- code review
+ more microbit device models
+ some raspi device model improvements
- sent patches for more Coverity issue fixes
- put together a list of source files still with legacy
non-QOM device models (about 60 files total)
- tagged QEMU 3.1.0 rc0
* VIRT-251 [aarch32 Hyp/running microvisors]
- tracked down a regression affecting L4Re guest: we had
misimplemented HCR.{VI,VF}. Sent patchset reverting the
broken version and implementing the correct semantics.
- finally tracked down why the 32-bit version of L4Re/Fiasco was
crashing -- we were incorrectly implementing Hyp mode as having
a banked r14, but it shares that register with User and System modes.
- These patches fix all the known issues with these guests.
thanks
-- PMM
=== Work done during the past week ===
* Resurrect code size optimization for fmul/dmul from Tony Wang:
+ clean up new testsuite directive andd testcases
* Fix -mslow-flash-data:
+ resurrect / rebase Arm internal patch to fix -mslow-flash-data
once and for all
+ many fixes to make it pass all testsuite with -mslow-flash-data without ICE
* Line management.
=== Plan for week 45 ===
* LLVM-432 (Support arithmetic on FileCheck regex variable):
+ extend testcase coverage (add tests for latest syntax change and
add more negative testing)
+ finish cleaning up the code
* Try to reproduce perf issue mentioned in week #30's weekly report on
latest perf
o Two days off.
o LLVM
* Machine Outliner on ARM prototype:
- catch-up after vacation
- re-based prototype branch on upstream
- Investigating issues in PIC mode
== This Week ==
* PR83750: CSE erf/erfc pair (6/10)
- Submitted patch upstream
* SVE ACLE (2/10)
- Started working on shift intrinsics
* GNU-235 (1/10)
- Cancelled card after I realized vrp does not support floating point ranges -:/
* Misc (1/10)
- Meetings
== Next Week ==
- PR83750: Address upstream comments
- GNU-405: Benchmark patch to provide more evidence to make it acceptable.
- SVE ACLE: Continue work on shift intrinsics.
[VIRT-241 # QEMU ARMv8.3 support ]
Finished filling out the sub-tasks for v8.3. Added some implementation
notes to some of those tasks as I reread the relevant documentation.
[VIRT-246 # ARMv8.1-LOR Limited Ordering Regions ]
Posted a trivial implementation.
[VIRT-247 # ARMv8.1-HPD and ARMv8.2-AA32HPD ]
Posted.
[Upstream]
Dirty tlb patches and decodetree changes squeeked in for softfreeze.
Another round of tlb flush reduction for aa64. This time exposing
asid's to the softmmu core and allowing it to flush when necessary.
Some more work toward moving x86 softmmu load sequences out of line.
The bulk of the code for 32-bit is now written, but it doesn't work yet.
Fix my thinko wrt divdeu and power7.
[GCC]
The cleanup part of my atomics patch set has been approved and committed.
Posted v3 of the out-of-line atomics part as well.
r~
Upstream Work ([VIRT-109])
==========================
- reviewed {Qemu-arm} {RFC v4 00/71} per-CPU locks Message-Id:
<20181025151103.GA19931@flamenco>
- this is a precursor to Emilio's {RFC 00/48} Plugin support
Message-Id: <20181025172057.20414-1-cota(a)braap.org>
[VIRT-109] https://projects.linaro.org/browse/VIRT-109
QEMU Tooling ([VIRT-252])
=========================
[VIRT-252] https://projects.linaro.org/browse/VIRT-252
QEMU plugin support ([VIRT-280])
- go through Emilio's {RFC 00/48} Plugin support Message-Id:
<20181025172057.20414-1-cota(a)braap.org> :todo
- port my example tools to his framework
[VIRT-280] https://projects.linaro.org/browse/VIRT-280
Kernel Debug via gdbstub
- started re-spin of [KVM/QEMU guest debug fix]
- reviewed/tested problem fixed by {Qemu-devel} {PATCH 0/5}
target/arm: KVM vs ARMISARegisters Message-Id:
<20181024113709.16599-1-richard.henderson(a)linaro.org>
- found a weird bug w.r.t single-stepping first instruction
- started down the debugging rabbit hole
[KVM/QEMU guest debug fix]
https://github.com/stsquad/qemu/tree/kvm/fix-breakpoints-v2
Other Tasks
===========
- Wrote up [KVM Forum 2018 report]
- started looking at {RFC PATCH v2 00/23} KVM: arm64: Initial support
for SVE guests Message-Id:
<1538141967-15375-1-git-send-email-Dave.Martin(a)arm.com>
[KVM Forum 2018 report]
https://collaborate.linaro.org/display/CR/20181024+KVM+Forum+2018
Completed Reviews [2/2]
=======================
{PATCH v2 0/3} Modern shell scripting (use $() instead of ``)
Message-Id: <20181018031723.23459-1-maozhongyi(a)cmss.chinamobile.com>
- CLOSING NOTE [2018-10-31 Wed 15:37]
The bit that touched bootstrap was fine
{Qemu-arm} {RFC v4 00/71} per-CPU locks
Message-Id: <20181025151103.GA19931@flamenco>
- CLOSING NOTE [2018-10-31 Wed 16:58]
Looks good, needs a minor tweak for linux-user mode. Will check
final patches on the next iteration.
Absences
========
- Christmas Holidays
- Connect BKK19 (1-5th April 2019)
Current Review Queue
====================
* {RFC 00/48} Plugin support
Message-Id: <20181025172057.20414-1-cota(a)braap.org>
* {RFC PATCH v2 00/23} KVM: arm64: Initial support for SVE guests
Message-Id: <1538141967-15375-1-git-send-email-Dave.Martin(a)arm.com>
* {PATCH 0/7} Acceptance Tests: basic architecture support
Message-Id: <20181004151429.7232-1-crosa(a)redhat.com>
* {PATCH v7 00/19} Fixing record/replay and adding reverse debugging
Message-Id: <20181010133333.24538.53169.stgit@pasha-VirtualBox>
* {PATCH v2 0/3} Bootstrap Python venv and acceptance/functional tests
Message-Id: <20181009041826.19462-1-crosa(a)redhat.com>
* {Qemu-arm} {PATCH 00/13} target/arm: Implement v8M stack limit checks
Message-Id: <20181002163556.10279-1-peter.maydell(a)linaro.org>
--
Alex Bennée
Progress:
* VIRT-65 [QEMU upstream maintainership]
- code review
- target-arm pull requests
- lots of pull request processing (softfreeze was this week)
- investigated and sent patches to fix a bug where a PC related
pullrequest was failing tests on my merge test setup (turned
out to be a build system issue where we were doing things in
configure that meant make didn't notice it needed to rerun it)
- some simple patches for coverity issues
thanks
-- PMM
[LLVM-203] Code-Size investigation with PGO
- Finished up the remain tasks and resolved the ticket.
- Tidied up the patches and added tests so that I can potentially
share them with other interested parties.
-- Writing tests took a lot longer than I thought as it involves
faking a profile and there were quite a few caveats to doing that.
Some prototyping in LLVM and LLD for some internal ABI discussions.
* 1 day off
== Progress ==
* FDPIC
- Cortex-M fix for binutils committed. uClibc-ng patch on-going
- GCC: handling feedback on v3 patches.
Trying to build/check xtensa uclinux toolchain to check my patches
do not affect it. No satisfactory reference build yet.
* GCC upstream validation:
- reported a few regressions
- one of last week's regressions is causing timeouts on some
validations, thus delaying the full queue. I haven't isolated the
cause yet
- dealing with some random results, again
* GCC:
- bug report on aarch64 about misaligned accesses. Waiting for more
details to reproduce the problem.
* misc (conf-calls, meetings, emails, ....)
- Benchmarking harness hopefully fixed
- reviewing infra script patches
- bugzilla cleanup
== Next ==
FDPIC:
- GCC: followup v3 patches
- uclibc-ng: look at how to test fdpic mode with openadk
- use qemu-system mode to run more tests
Benchmarking:
- fix harness until they support gcc-8
=== Work done during this past week ===
* GNU-296 / GCC PR85434 / CVE-2018-12886: upstream review
+ avoid useless cmp after eors
+ fix another missing earlyclobber
+ full Thumb-1, Thumb-2 and Arm bootstrap with testing with and
without -fPIC, with and without -fstack-protector-all
* Continue patch to further update cpus and architectures in bfd:
external review
+ also teach GAS about Armv5TEJ and newer wrt. bfd architectures tags
+ fix ld action in run_dump_test
+ add testing for all this and submit for external review
* Resurrect code size optimization for fmul/dmul from Tony Wang:
+ rebase on trunk
* Line management
=== Plan for week 43 ===
* LLVM-432 (Support arithmetic on FileCheck regex variable):
+ extend testcase coverage (add tests for latest syntax change and
add more negative testing)
+ finish cleaning up the code
* Try to reproduce perf issue mentioned in week #30's weekly report on
latest perf
* Line management
Progress:
* Attended OSS Europe/KVM Forum
- as usual, a good week (helpful conversations, interesting sessions)
- full conference writeup later in the week
thanks
-- PMM
[VIRT-198 # QEMU: SVE Emulation Support ]
Last of the patches merged to mainline. Epic is now closed.
[VIRT-282 # QEMU: Accelerate TCG with KVM ]
A hallway talk with Paolo lead to a write-up, and Alex encouraged me to create
the epic. The epic description contains a link to the write-up, if anyone is
interested. I'd like to at least create a vm, measure some round-trip costs,
and properly gauge the level of difficulty. Beyond that... we'll see.
[Upstream]
Patch review:
- risc-v decodetree patches v2.
Produced some patches against decodetree itself in response.
I'm hopeful to see a much cleaner v3.
- per-cpu locks
[KVM Forum]
- Unsurprisingly, lots of people worked on speculation mitigation this year.
- Lots of focus on "ram", and the allocation and management thereof.
- Four talks on improving nested virtualization.
- The rest to follow in the trip report.
r~
== Progress ==
* FDPIC
- Posted binutils and uClibc-ng patches to fix cortex-M support, under
discussion
- GCC: handling feedback on v3 patches.
Experimented thumb-1 builds, failed.
* GCC upstream validation:
- reported a few regressions
- dealing with some random results, again
* GCC:
- bug report on aarch64 about misaligned accesses. Waiting for more
details to reproduce the problem.
* misc (conf-calls, meetings, emails, ....)
- Working on fixes of our benchmarking harness to support new gcc-8 releases.
== Next ==
FDPIC:
- GCC: followup v3 patches
- uclibc-ng: look at how to test fdpic mode with openadk
- use qemu-system mode to run more tests
Benchmarking:
- fix harness until they support gcc-8
