All posts by jake

LTTng 2.11.0 “Lafontaine” released

Post Syndicated from jake original https://lwn.net/Articles/802633/rss

After more than two years of development, the Linux trace toolkit next generation (LTTng)
project has released version 2.11.0 of the kernel and user-space tracing
tool. The release covers the LTTng tools, LTTng user-space tracer, and
LTTng kernel modules. It includes a number of new features that are
described in the announcement including session rotation, dynamic user-space tracing,
call-stack capturing for the kernel and user space, improved networking
performance, NUMA awareness for user-space tracing buffer allocation, and
more. “The biggest feature of this release is the long-awaited session
rotation support. Session rotations now allow you to rotate an
ongoing tracing session much in the same way as you would rotate
logs.

The ‘lttng rotate’ command rotates the current trace chunk of
the current tracing session. Once a rotation is completed, LTTng does
not manage the trace chunk archive anymore: you can read it, modify it,
move it, or remove it.

Because a rotation causes the tracing session’s current sub-buffers
to be flushed, trace chunk archives are never redundant, that is, they
do not overlap over time, unlike snapshots.

Once a rotation is complete, offline analyses can be performed on
the resulting trace, much like in ‘normal’ mode. However, the big
advantage is that this can be done without interrupting tracing, and
without being limited to tools which implement the ‘live’ protocol.”

Ubuntu 19.10 (Eoan Ermine) released

Post Syndicated from jake original https://lwn.net/Articles/802583/rss

Ubuntu has announced the release of 19.10 “Eoan Ermine” in desktop and server editions as well as all of the different flavors: Ubuntu Budgie, Kubuntu, Lubuntu, Ubuntu Kylin, Ubuntu MATE,
Ubuntu Studio, and Xubuntu. “The Ubuntu kernel has been updated to the 5.3 based Linux kernel, and
our default toolchain has moved to gcc 9.2 with glibc 2.30. Additionally,
the Raspberry Pi images now support the new Pi 4 as well as 2 and 3.

Ubuntu Desktop 19.10 introduces GNOME 3.34 the fastest release yet with
significant performance improvements delivering a more responsive
experience. App organisation is easier with the ability to drag and drop
icons into categorised folders and users can select light or dark Yaru
theme variants. The Ubuntu Desktop installer also introduces installing
to ZFS as a root filesystem as an experimental feature.” More information can also be found in the release notes.

Security updates for Thursday

Post Syndicated from jake original https://lwn.net/Articles/802537/rss

Security updates have been issued by Arch Linux (sudo), Debian (libsdl1.2 and libsdl2), Mageia (e2fsprogs, kernel, libpcap and tcpdump, nmap, and sudo), openSUSE (GraphicsMagick and sudo), Oracle (java-1.8.0-openjdk, java-11-openjdk, jss, and kernel), Red Hat (java-1.8.0-openjdk and java-11-openjdk), Scientific Linux (jss), SUSE (gcc7 and libreoffice), and Ubuntu (leading to a double-free, libsdl1.2, and tiff).

[$] WireGuard and the crypto API

Post Syndicated from jake original https://lwn.net/Articles/802376/rss

When last we looked in on the progress of
the WireGuard VPN tunnel toward the
mainline kernel, it seemed like the main sticking point had been overcome. The Zinc cryptography API used by WireGuard was
generally seen as a duplication of effort with the existing kernel
cryptographic algorithms, so an effort to rework Zinc to use that existing
code seemed destined to route around that problem and bring WireGuard to
the mainline. In the six months since then, though, things have gone
fairly quiet in WireGuard-land; that all changed based on a conversation at
the recent Kernel Recipes
conference in Paris.

[$] FPGAs and free software

Post Syndicated from jake original https://lwn.net/Articles/801928/rss

The problems with field-programmable
gate arrays
(FPGAs) is not exactly an obvious talk topic for a
graphics-related conference like the 2019 X.Org Developers Conference (XDC). Ben
Widawsky acknowledged that, but said that he sees parallels in the
situation with FPGA support in the free-software world and the situation with
graphics hardware support in the past. It is his hope that the tools for
developing with FPGAs can make the same journey that graphics drivers have
made over the last two decades or so.

Understanding Scheduling Behavior with SchedViz (Google Open Source Blog)

Post Syndicated from jake original https://lwn.net/Articles/802022/rss

The Google Open Source Blog has an announcement of the release of the SchedViz tool that is used internally at the company “to discover many opportunities for better scheduling choices and to root-cause many latency issues“. SchedViz provides a GUI to explore kernel traces: “The SchedViz UI displays collections in several ways. A zoomable and pannable heatmap shows system cores on the y-axis, and the trace duration on the x-axis. Each core in the system has a swim-lane, and each swim-lane shows CPU utilization (when that CPU is being kept busy) and wait-queue depth (how many threads are waiting to run on that CPU.) The UI also includes a thread list that displays which threads were active in the heatmap, along with how long they ran, waited to run, and blocked on some event, and how many times they woke up or migrated between cores. Individual threads can be selected to show their behavior over time, or expanded to see their details.

[$] An update on the input stack

Post Syndicated from jake original https://lwn.net/Articles/801767/rss

The input stack for Linux is an essential part of interacting with our
systems, but it is also an area that is lacking in terms of developers.
There has been progress over the last few years, however; Peter Hutterer
from Red Hat came to the 2019 X.Org
Developers Conference to talk about some
of the work that has been done. He gave a status report on the input
stack that covered development work that is going on now as well as things
that have been completed in the last two years or so. Overall, things are
looking pretty good for input on Linux, though the “bus factor” for the
stack is alarmingly low.

[$] Free software support for virtual and augmented reality

Post Syndicated from jake original https://lwn.net/Articles/801494/rss

A talk at the recent X.Org Developers Conference in
Montréal, Canada
looked at support for “XR” in free software. XR is an umbrella term that
includes both virtual reality (VR) and augmented reality (AR). In the
talk, Joey
Ferwerda and Christoph Haag from Collabora gave an overview of XR and
the
Monado project that provides support for
those types of applications.

[$] Starting The Document Collective

Post Syndicated from jake original https://lwn.net/Articles/801016/rss

The Document Foundation (TDF) is
the home of the LibreOffice
free-software office suite; it provides financial, governance, and
other administrative services to LibreOffice. The foundation was
established in part to ensure that commercial entities did not have undue
influence on the project, which limited the types of activities in which it
can engage. In particular, selling branded versions of LibreOffice in the
macOS and Windows app stores has not been something that TDF could tackle.
The TDF
board of directors
is looking to change that with the creation of a
new entity, The Document Collective (TDC), to engage in commercial activity that
is complementary to that of TDF members—hopefully as an income source to
help support TDF.

[$] PostgreSQL considers seccomp() filters

Post Syndicated from jake original https://lwn.net/Articles/800916/rss

A discussion on the pgsql-hackers mailing
list
at the end of August is another reminder that the suitability of
seccomp()
filters is likely more narrow than was hoped. Applying filters to
the PostgreSQL database is difficult for a number of reasons and the
benefit for the project and its users is not entirely clear. The
discussion highlights the tradeoffs inherent in adding system-call
filtering to a complex software suite; it may help crystallize the thinking
of other projects that are also
looking at supporting seccomp() filters.

RPM 4.15.0 released

Post Syndicated from jake original https://lwn.net/Articles/800735/rss

After “more than two years in development and half a year in testing“, version 4.15.0 of the RPM package manager has been released. It has a wide range of new features, including faster parallel builds; support for %elif, %elifos, and %elifarch statements in RPM spec files; new %patchlist and %sourcelist sections; experimental support for non-privileged operation in a chroot() environment; and, of course, plenty of bug fixes and such. More details can be found in the release notes.

Purism’s Librem 5 phone starts shipping—a fully open GNU/Linux phone (Ars Technica)

Post Syndicated from jake original https://lwn.net/Articles/800725/rss

Ars Technica reports on the Librem 5 smartphone from Purism, which has begun shipping. The article provides an initial review of the phone, with pictures of the interface and hardware inside the case. “The Librem 5 is unlike anything else on the market. Not only is it one of the only smartphones on Earth that doesn’t ship with Android, a fork of Android, or iOS—Purism’s commitment to 100% open software, with no binary blobs, puts severe restrictions on what hardware it can use. Android’s core might be open source, but it was always built for wide adoption above all else, with provisions for manufacturers to include as much proprietary code as they want. Purism’s demand that everything be open means most of the major component manufacturers were out of the question.

Perhaps because of the limited hardware options, the internal construction of the Librem 5 is absolutely wild. While smartphones today are mostly a single mainboard with every component integrated into it, the Librem 5 actually has a pair of M.2 slots that house full-size, off-the-shelf LTE and Wi-Fi cards for connectivity, just like what you would find in an old laptop. The M.2 sockets look massive on top of the tiny phone motherboard, but you could probably replace or upgrade the cards if you wanted.”

How to contribute to Fedora (Fedora Magazine)

Post Syndicated from jake original https://lwn.net/Articles/800717/rss

Over at Fedora Magazine, Ben Cotton has an article on contributing to the Fedora distribution. Obviously, it is pretty Fedora-specific, but the general ideas can be applied to other distributions and/or projects. He lists several areas where contributors are needed—beyond just the obvious candidates: “Cooperative effort is a hallmark of open source communities. One of the best ways to contribute to any project is to help other users. In Fedora, that can mean answering questions on the Ask Fedora forum, the users mailing list, or in the #fedora IRC channel. Many third-party social media and news aggregator sites have discussion related to Fedora where you can help out as well.

[$] Fixing getrandom()

Post Syndicated from jake original https://lwn.net/Articles/800509/rss

A report of
a boot hang in the 5.3 series has led to an enormous, somewhat contentious
thread on the linux-kernel mailing list. The proximate cause was some changes that made the
ext4 filesystem do less I/O early in the boot phase, incidentally causing
fewer interrupts, but the
underlying issue was the getrandom()
system call
, which was blocking until the /dev/urandom pool
was initialized—as designed. Since the system in question was not
gathering enough entropy due to the lack of unpredictable interrupt
timings, that would hang more or less forever. That has called into
question the design and implementation of getrandom().