All posts by daroc

[$] LLVM improvements for BPF verification

Post Syndicated from daroc original https://lwn.net/Articles/974945/

Alan Jowett gave a remote presentation at the 2024
Linux Storage,
Filesystem, Memory Management, and BPF Summit about what features could be
added to LLVM to make writing BPF programs easier. While there is nothing specific
to LLVM about BPF code (and the next session in the track was led by GCC
developer José Marchesi about better support for that compiler), LLVM is currently the most
common way to turn C code into BPF bytecode. That translation, however, runs
into problems when the BPF verifier cannot understand the code LLVM’s
optimizations produce.

[$] Recent improvements to BPF’s struct_ops mechanism

Post Syndicated from daroc original https://lwn.net/Articles/974848/

Kui-Feng Lee spoke early in the BPF track at the 2024
Linux Storage,
Filesystem, Memory Management, and BPF Summit about some of the
recent improvements to BPF. These changes were largely driven by the
sched_ext work that David Vernet had covered in
the previous talk. Lee focused on changes relevant to struct_ops
programs, but several of those changes apply to all BPF programs.

[$] What’s scheduled for sched_ext

Post Syndicated from daroc original https://lwn.net/Articles/974387/

David Vernet’s second talk at the 2024
Linux Storage,
Filesystem, Memory Management, and BPF Summit was a summary of the state of
sched_ext, the extensible BPF scheduler that LWN
covered a in early May. In short, sched_ext is intended as a platform for
rapid experimentation with schedulers, and a tool to let performance-minded
administrators customize the scheduler to their workload. The patch set has seen
several revisions, becoming more generic and powerful over time.
Vernet spoke about what has been done in the past year,
and what is still missing before sched_ext can be considered pretty much
complete.

[$] Virtual machine scheduling with BPF

Post Syndicated from daroc original https://lwn.net/Articles/974363/

Vineeth Pillai gave a remote talk at the 2024
Linux Storage,
Filesystem, Memory Management, and BPF Summit explaining how BPF could be
used to improve the performance of virtual machines (VMs). Pillai has

a patch
set designed to let guest and host machines share scheduling information in
order to eliminate some of the overhead of running in a VM. The assembled
developers had several comments on the design, but seemed overall to approve of
the prospect.

[$] A plan to make BPF kfuncs polymorphic

Post Syndicated from daroc original https://lwn.net/Articles/974102/

David Vernet kicked off the BPF track at 2024’s BPF track at the
Linux Storage,
Filesystem, Memory Management, and BPF Summit
with a
talk about polymorphic kfuncs — or, with less jargon, kernel functions that can
be called from BPF which use different implementations depending on context.
He explained how this would be useful to
the sched_ext BPF scheduling framework,
but expected it to be helpful in
other areas as well.

[$] GitLab CI for the kernel

Post Syndicated from daroc original https://lwn.net/Articles/972713/

Working on the Linux kernel has always been unlike working on
many other software projects.
One particularly noticeable difference is the decentralized nature of the
kernel’s testing infrastructure. Projects such as

syzkaller, KernelCI,
or the kernel self tests
test the kernel in different ways. On February 28, Helen
Koike

posted a patch set that would add continuous integration (CI) scripts for
the whole kernel. The response was generally positive, but several people
suggested changes.

Security updates for Friday

Post Syndicated from daroc original https://lwn.net/Articles/974055/

Security updates have been issued by Fedora (chromium, firefox, and podman), Mageia (chromium-browser-stable, ghostscript, and java-1.8.0, java-11, java-17, java-latest), Red Hat (bind, Firefox, firefox, gnutls, httpd:2.4, and thunderbird), SUSE (glibc, opera, and python-Pillow), and Ubuntu (dotnet7, dotnet8, linux, linux-aws, linux-aws-5.4, linux-azure, linux-azure-5.4,
linux-bluefield, linux-gcp, linux-gcp-5.4, linux-gkeop, linux-hwe-5.4,
linux-ibm, linux-ibm-5.4, linux-iot, linux-kvm, linux-oracle,
linux-oracle-5.4, linux-raspi, linux-raspi-5.4, linux-xilinx-zynqmp, linux, linux-aws, linux-aws-6.5, linux-azure, linux-azure-6.5, linux-gcp,
linux-gcp-6.5, linux-hwe-6.5, linux-laptop, linux-lowlatency,
linux-lowlatency-hwe-6.5, linux-nvidia-6.5, linux-oem-6.5, linux-oracle,
linux-oracle-6.5, linux-raspi, linux-signed, linux-signed-aws,
linux-signed-aws-6.5, linux-starfive, linux-starfive-6.5, linux, linux-aws, linux-azure-4.15, linux-gcp-4.15, linux-hwe, linux-kvm,
linux-oracle, linux, linux-aws, linux-kvm, linux-lts-xenial, and linux, linux-azure, linux-azure-5.15, linux-azure-fde,
linux-azure-fde-5.15, linux-gcp, linux-gcp-5.15, linux-gkeop,
linux-gkeop-5.15, linux-hwe-5.15, linux-ibm, linux-ibm-5.15,
linux-intel-iotg, linux-kvm, linux-lowlatency, linux-lowlatency-hwe-5.15,
linux-nvidia, linux-oracle, linux-raspi).

[$] Portable LLMs with llamafile

Post Syndicated from daroc original https://lwn.net/Articles/971195/

Large language models (LLMs) have been the subject of much discussion and
scrutiny recently. Of particular interest to open-source enthusiasts are the
problems with running LLMs on one’s own hardware — especially when doing so
requires NVIDIA’s proprietary CUDA toolkit, which remains unavailable in many
environments.
Mozilla has developed
llamafile as a
potential solution to these problems. Llamafile can compile LLM weights
into portable, native executables for easy integration, archival, or
distribution. These executables can take advantage of supported GPUs when
present, but do not require them.

Security updates for Friday

Post Syndicated from daroc original https://lwn.net/Articles/973206/

Security updates have been issued by AlmaLinux (container-tools:4.0, container-tools:rhel8, git-lfs, glibc, libxml2, nodejs:18, and nodejs:20), Debian (dav1d and libpgjava), Fedora (kernel and pypy), Red Hat (glibc and nodejs:16), SUSE (ffmpeg, ffmpeg-4, ghostscript, go1.21, go1.22, less, python-python-jose, python-Werkzeug, and sssd), and Ubuntu (fossil, glib2.0, and libspreadsheet-parsexlsx-perl).

[$] Systemd heads for a big round-number release

Post Syndicated from daroc original https://lwn.net/Articles/971866/

The

systemd project is preparing for a new release.

Version 256-rc1 was released
on April 25 with a large number of changes and new features. Most of the
changes relate to security, easier configuration, unprivileged access to system
resources, or all three of these. Users of systemd will find setting up
containers — even without root access — much simpler and more secure.

Stenberg: I survived curl up 2024

Post Syndicated from daroc original https://lwn.net/Articles/972603/

Daniel Stenberg has

posted a report about the recent curl up conference about
curl development. It was held over two days in
Stockholm. The report has short summaries of the talks with links to the
recordings.

curl up is never a big meeting/conference but we have in the past
sometimes been around twenty-five attendees. This year’s amount of
fifteen was the smallest so far, but in this small set of people we
have a set of long-term well-known curl contributors. It is not a
big list of attendees that creates a good curl up.

Eelco Dolstra steps down from NixOS Foundation board

Post Syndicated from daroc original https://lwn.net/Articles/971973/

The NixOS Foundation board

announced on April 30 that Eelco Dolstra is stepping down from the board
following the recent calls for his resignation.

Eelco is the principal author of Nix and undoubtedly a central figure in the
ecosystem that grew around it. We confirm that Eelco showed no intention to be
perceived as or act like the BDFL [Benevolent Dictator for Life]
of the Nix ecosystem, or the Nix code base. To
commit to that in a timely manner, he has decided to formally step down from the
board.

The board also announced its intent to set up new, explicit governance for the
project, answerable to the community:

We will appoint a constitutional assembly within the next 14 days.
Its task will be to set up a new governance structure, run by the
community, that is capable of serving the community’s needs. Once
established, we will delegate our power to institutions within that
new structure. This entire process will take place in a public space,
such that it’s traceable for anyone concerned. We are committed to
listening to everyone who may help with solving the problems the
community is facing.

[$] A leadership crisis in the Nix community

Post Syndicated from daroc original https://lwn.net/Articles/970824/

On April 21, a group of anonymous authors and non-anonymous signatories published
a lengthy open letter to the

Nix community
and Nix founder Eelco Dolstra calling for his resignation from the project. They
claimed ongoing problems with the project’s leadership, primarily focusing on the
way his actions have allegedly
undermined people nominally empowered to perform various
moderation and governance tasks. Since its release, the letter has gained
more than 100 signatures.

Security updates for Friday

Post Syndicated from daroc original https://lwn.net/Articles/971289/

Security updates have been issued by Debian (knot-resolver, pdns-recursor, and putty), Fedora (xen), Mageia (editorconfig-core-c, glibc, mbedtls, webkit2, and wireshark), Oracle (buildah), Red Hat (buildah and yajl), Slackware (libarchive), SUSE (dcmtk, openCryptoki, php7, php74, php8, python-gunicorn, python-idna, qemu, and thunderbird), and Ubuntu (cryptojs, freerdp2, nghttp2, and zabbix).

[$] Python JIT stabilization

Post Syndicated from daroc original https://lwn.net/Articles/970397/

On April 11, Brandt Bucher posted
PEP 744 (“JIT Compilation”),
which summarizes the current state of Python’s new
copy-and-patch just-in-time (JIT) compiler. The JIT is currently
experimental, but the PEP proposes some criteria for the circumstances under which it
should become a non-experimental part of Python.

The discussion of the PEP hasn’t
reached a conclusion, but
several members of the community have already raised questions
about how the JIT would fit into future iterations of the Python language.

GitHub comments used to distribute malware (BleepingComputer)

Post Syndicated from daroc original https://lwn.net/Articles/971008/

BleepingComputer

reported on April 20 that some malware was being distributed via GitHub.
Uploading files as part of a comment gives them a URL that appears to be
associated with a repository, even if the comment is never posted.

A GitHub flaw, or possibly a design decision, is being abused by threat actors
to distribute malware using URLs associated with Microsoft repositories, making
the files appear trustworthy.

While most of the malware activity has been based around the Microsoft GitHub
URLs, this “flaw” could be abused with any public repository on GitHub, allowing
threat actors to create very convincing lures.