Post Syndicated from corbet original https://lwn.net/Articles/991199/

One concern that has often been expressed about the Rust language is that
there is only one compiler for it. That makes it hard to say what the
standard version of the language is and restricts the architectures that
can be targeted by Rust code to those that the available compiler supports.
Adding a Rust frontend to GCC would do much to address those concerns; at
the 2024 GNU Tools
Cauldron, Pierre-Emmanuel Patry gave an update on the state of that
work and what its objectives are.

Post Syndicated from corbet original https://lwn.net/Articles/992444/

Security updates have been issued by Debian (debian-security-support, nghttp2, and sqlite3), Oracle (cups-filters, kernel, and osbuild-composer), SUSE (openssl-3), and Ubuntu (bubblewrap, flatpak and python2.7, python3.5).

Post Syndicated from corbet original https://lwn.net/Articles/991301/

Linus Torvalds released
6.12-rc1 and closed the 6.12 merge window on September 29; at that
point, 11,260 non-merge change sets had been pulled into the mainline for
the 6.12 release. That is the lowest number of merge-window changes since
5.17-rc1 in January 2022, which brought in 11,068 changesets. Nonetheless,
6.12 brings a number of interesting changes, many of which were included in
the roughly 4,500 changes merged since the
summary of the first half of the 6.12 merge window was written.

Post Syndicated from corbet original https://lwn.net/Articles/992194/

The Arch Linux project has announced that Valve will be helping the
distribution with a couple of important initiatives:

Valve is generously providing backing for two
critical projects that will have a huge impact on our distribution: a
build service infrastructure and a secure signing enclave. By supporting
work on a freelance basis for these topics, Valve enables us to work on
them without being limited solely by the free time of our volunteers.

Post Syndicated from corbet original https://lwn.net/Articles/992185/

Linus has released 6.12-rc1 and closed the
merge window for this release.

Despite conference travel (both for me and several maintainers),
things seemed to go mostly fairly normally. There’s a couple of
notable new features in here: For one thing, PREEMPT_RT is now
mainlined and enabled as a config option (you do need to enable
“EXPERT” to get the question). For another, sched_ext also got
merged.

Post Syndicated from corbet original https://lwn.net/Articles/992120/

Michał Górny describes
the challenges involved in transitioning Gentoo to year-2038-safe time
representations:

There is a general agreement that the way forward is to change
time_t to a 64-bit type. Musl has already switched to that, glibc
supports it as an option. A number of other distributions such as
Debian have taken the leap and switched. Unfortunately,
source-based distributions such as Gentoo don’t have it that
easy. So we are still debating the issue and experimenting, trying
to figure out a maximally safe upgrade path for our users.

Unfortunately, that’s nowhere near trivial. Above all, we are
talking about a breaking ABI change.

Post Syndicated from corbet original https://lwn.net/Articles/991205/

The extensible scheduler class (sched_ext)
enables the implementation of CPU schedulers as a set of BPF programs
loaded from user space; it first hit the mailing lists in late 2022.
Sched_ext has engendered its share of controversy since, but is currently
slated to be part of the 6.12 kernel release. At the 2024 Linux Plumbers Conference, the growing
sched_ext community held one of its first public gatherings; sched_ext
would appear to have launched a new burst of creativity in scheduler
design.

Post Syndicated from corbet original https://lwn.net/Articles/991775/

Here’s a
post on the Google Security Blog on how switching to a memory-safe
language can quickly reduce vulnerabilities in a project, even if a large
body of older code persists.

This leads to two important takeaways:

• The problem is overwhelmingly with new code, necessitating a
  fundamental change in how we develop code.

• Code matures and gets safer with time, exponentially, making the
  returns on investments like rewrites diminish over time as code gets
  older.

For example, based on the average vulnerability lifetimes, 5-year-old code
has a 3.4x (using lifetimes from the study) to 7.4x (using lifetimes
observed in Android and Chromium) lower vulnerability density than new
code.

Post Syndicated from corbet original https://lwn.net/Articles/990791/

The LWN.net Weekly Edition for September 26, 2024 is available.

Post Syndicated from corbet original https://lwn.net/Articles/991062/

The project to enable the writing of kernel code in Rust has been underway
for several years, and each kernel release includes more Rust code. Even
so, some developers have expressed frustration at the time it takes to get
new functionality merged, and an air of uncertainty still hangs over
the project. At the 2024 Maintainers Summit, Miguel Ojeda led a discussion
on the status of Rust in the kernel and whether the time had come to stop
considering it an experimental project. There were not answers to all of the
questions, but it seems clear that Rust in the kernel will continue
steaming ahead.

Post Syndicated from corbet original https://lwn.net/Articles/991492/

Security updates have been issued by Gentoo (GCC, Hunspell, Tor, and ZNC), SUSE (apr-devel, cargo-c, chromedriver, firefox, kernel, libecpg6, libmfx, onefetch, postgresql12, postgresql13, postgresql14, postgresql15, postgresql16, python310-azure-identity, python39, qemu, rage-encryption, stgit, and system-user-zabbix), and Ubuntu (kernel, linux-ibm-5.15, linux-oracle-5.15, linux-xilinx-zynqmp, linux-lowlatency, linux-lowlatency-hwe-5.15, linux-raspi, and py7zr).

Post Syndicated from corbet original https://lwn.net/Articles/991033/

Konstantin Ryabitsev started a session on development tooling at the 2024
Maintainers Summit by saying that he does not want to be a “wrecking ball”.
If a given workflow is working for people, he does not want to try to force
any sort of change. That said, he has ideas for how he can continue his
work on providing better tooling for the development community.

Post Syndicated from corbet original https://lwn.net/Articles/990750/

As of this writing, 6,778 non-merge changesets have been pulled into the
mainline kernel for the 6.12 release — over half of the work that had been
staged in linux-next prior to the opening of the merge window. There has
been a lot of refactoring and cleanup work this time around, but also some
significant changes. Read on for a summary of the first half of the 6.12
merge window.

Post Syndicated from corbet original https://lwn.net/Articles/990802/

The kernel normally sits firmly between user space and the system’s
peripheral devices, and provides a standard interface to those devices. At
times, though, a more direct interface to a device is desired — but such
interfaces can be controversial. At the 2024 Maintainers Summit, the
assembled developers considered a specific case — the proposed fwctl subsystem — as well as the role of such
drivers in general.

Post Syndicated from corbet original https://lwn.net/Articles/990985/

On September 19, Thomas Gleixner delivered the pull request for the
realtime preemption enablement patches to Linus Torvalds — in printed form,
wrapped in gold, with a ribbon, as Torvalds had requested. It was a
significant milestone, marking the completion of a project that required
20 years of effort. Congratulations are due to everybody involved.

Torvalds acted on
the pull request the following morning.

Post Syndicated from corbet original https://lwn.net/Articles/990599/

Tracking of regressions seems like an important task for any project; there
is no other way to ensure that known problems are fixed. At the 2024
Maintainers Summit, though, Thorsten Leemhuis, who has been doing that work
for the kernel, expressed some doubts about whether it is worth continuing.
The result was an energetic session on how regression tracking should be
done better, and how this work should be supported.

Post Syndicated from corbet original https://lwn.net/Articles/990788/

Version 47 of the GNOME desktop
has been released. Changes include configurable accent colors, better
small-screen support, some performance improvements, new file open and save
dialogs, and more.

Post Syndicated from corbet original https://lwn.net/Articles/989982/

The LWN.net Weekly Edition for September 19, 2024 is available.

Post Syndicated from corbet original https://lwn.net/Articles/990379/

A Linux system is made up of a large number of interdependent components,
all of which must support each other well. It can thus be surprising that,
it seems, the developers working on those components do not often speak
with each other. In the hope of improving that situation, efforts have
been made in recent years to attract toolchain developers to the
kernel-heavy Linux Plumbers Conference. This year, though, the opposite
happened as well: the 2024
GNU Tools Cauldron hosted a discussion where kernel developers were
invited to discuss their needs.

Post Syndicated from corbet original https://lwn.net/Articles/990343/

The generation of binary code for the kernel’s BPF virtual machine has been
limited to the Clang compiler since the beginning; even developers who
use GCC to build kernels must use Clang to compile to BPF. Work has
been underway for some years on adding a BPF backend to GCC as well; the
developers involved ran a session at the 2024 GNU Tools Cauldron to
provide an update on that project. It would seem that the BPF backend is
close to being ready for production use.