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Kernel: NOVA, Genpool Subsystem, Automotive Grade Linux

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Linux
  • [Older] The NOVA filesystem [Ed: used to be behind paywall]

    Nonvolatile memory offers the promise of fast, byte-addressable storage that persists over power cycles. Taking advantage of that promise requires the imposition of some sort of directory structure so that the persistent data can be found. There are a few approaches to the implementation of such structures, but the usual answer is to employ a filesystem, since managing access to persistent data is what filesystems were created to do. But traditional filesystems are not a perfect match to nonvolatile memory, so there is a natural interest in new filesystems that were designed for this media from the beginning. The recently posted NOVA filesystem is a new entry in this race.

    The filesystems that are currently in use were designed with a specific set of assumptions in mind. Storage is slow, so it is worth expending a considerable amount of CPU power and memory to minimize accesses to the underlying device. Rotational storage imposes a huge performance penalty on non-sequential operations, so there is great value in laying out data consecutively. Sector I/O is atomic; either an entire sector will be written, or it will be unchanged. All of these assumptions (and more) are wired deeply into most filesystems, but they are all incorrect for nonvolatile memory devices. As a result, while filesystems like XFS or ext4 can be sped up considerably on such devices, the chances are good that a filesystem designed from the beginning with nonvolatile memory in mind will perform better and be more resistant to data corruption.

    NOVA is intended to be such a filesystem. It is not just unsuited for regular block devices, it cannot use them at all, since it does not use the kernel's block layer. Instead, it works directly with storage mapped into the kernel's address space. A filesystem implementation gives up a lot if it avoids the block layer: request coalescing, queue management, prioritization of requests, and more. On the other hand, it saves the overhead imposed by the block layer and, when it comes to nonvolatile memory performance, cutting down on CPU overhead is a key part of performing well.

  • [Older] The kernel's genpool subsystem

    The kernel is a huge program; among other things, that means that many problems encountered by a kernel developer have already been solved somewhere else in the tree. But those solutions are not always well known or documented. Recently, a seasoned developer confessed to having never encountered the "genpool" memory allocator. This little subsystem does not appear in the kernel documentation, and is likely to be unknown to others as well. In the interest of fixing both of those problems, here is an overview of genpool (or "genalloc") and what it does.

    There are a number of memory-allocation subsystems in the kernel, each aimed at a specific need. Sometimes, however, a kernel developer needs to implement a new allocator for a specific range of special-purpose memory; often that memory is located on a device somewhere. The author of the driver for that device can certainly write a little allocator to get the job done, but that is the way to fill the kernel with dozens of poorly tested allocators. Back in 2005, Jes Sorensen lifted one of those allocators from the sym53c8xx_2 driver and posted it as a generic module for the creation of ad hoc memory allocators. This code was merged for the 2.6.13 release; it has been modified considerably since then.

  • Advancing Connected-Car Technology Through Linux

    Automotive Grade Linux—which just launched its UCB 4.0 platform—and GENIVI take somewhat different paths to accelerate the development and adoption of an open software stack for IVI systems.

Raspberry Pi Zero and Zero W: Linux computing in an even smaller package

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Linux
Hardware

When the original Raspberry Pi (Rpi) became available in 2012, it was amazing that a Linux computer could fit in the palm of your hand for the low, low price of $35. On the other hand, if you’re a student without a real job, for which these boards were in part intended, $35 can still be a lot of money. To bring this cost down even further, the RPi team announced the RPi Zero in late 2015, which is available for $5, and even came as a “gift” on the cover of that December’s MagPi magazine.

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Linux Mint-Based feren OS Gets Upgraded to Linux Mint 18.2, USB Boot Improved

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Linux

The developers of the feren OS GNU/Linux distribution based on the popular Linux Mint operating system announced the release of August 2017's snapshot ISO with many enhancements and updated components.

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SBC expands on 2GHz Rockchip RK3399 with eye-popping feature list

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Android
Linux

Videostrong’s new SBC runs Android 7.1 or Ubuntu on the RK3399 with 2GB RAM plus GbE, WiFi, BT, HDMI 2.0, DP 1.2, MIPI-CSI, USB 3.0, and mini-PCIe.

Shenzhen-based Android set-top box maker Videostrong has released a “VS-RD-RK3399” development kit built around the Rockchip RK3399. The OEM focused single-board computer sells for $250 individually, but can be had for $149 in 1,000+ OEM volumes. The kit is available in otherwise identical Android 7.1 and Ubuntu with Linux 4.4.55 SKUs, with the latter drawing on Rockchip’s increasingly capable Linux support.

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Linux Foundation's Dronecode, Ethereum Blockchain, and Kernel Changes

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Linux

Chakra Linux: Its Own Beast, Its Own Beauty

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Linux

There are so many Linux distributions available—so many, in fact, that it can become a bit of a challenge to find the one right for you. After you’ve looked at them enough, it seems the variations tend to blur together, such that one flavor of Linux is only a slight shift away from another.

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Debian GNU/Linux Running On Mobile Devices Like PocketCHIP, Samsung Galaxy, ZeroPhone, & Pyra

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GNU
Linux
Debian

Debian is also called the universal operating system as it is used as a base for hundreds of Linux distributions. So, this claim also underlines that Debian should run on mobile devices too–right? Well, Debian developers are continuously working to add support for new devices and adapt it as per hardware and GUI capabilities of different devices.

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5 Best Vector Graphics Editors for Linux

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Linux

Here's a list of the best vector graphics software for Linux that can be used as Adobe Illustrator alternative for Linux.
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Linux-loving lecturer 'lost' email, was actually confused by Outlook

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Linux

ON-CALL Friday means a few things at El Reg: a new BOFH. A couple of beers. And another instalment of On-Call, our weekly column in which we take reader-contributed tales of being asked to do horrible things for horrible people, scrub them up and hope you click.

This week, meet “Newt” who a dozen or more years ago worked at a College that “decided to migrate from a Linux system to Microsoft Outlook with an Exchange back end.”

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More in Tux Machines

Software: GnuCash, Minuet, Citrix, and YouTube

  • Escape from QuickBooks (with data in hand)
    When a small business contemplates getting away from a proprietary accounting tool like QuickBooks in favor of free software like GnuCash, the first order of business is usually finding a way to liberate that business's accounting data for input into a new system. Strangely enough, Intuit, the creator of QuickBooks, never quite got around to making that easy to do. But it turns out that, with a bit of effort, this move can be made. Getting there involves wandering through an undocumented wilderness; this article is at attempt to make things easier for the next people to come along.
  • Minuet – a guitar adventure
    As you remember from my last post, minuet currently supports multiple plugins to display its exercises. To change from one plugin to another, all you have to do is to press on the desired instrument name: for now, only “Guitar” and “Piano” are available.
  • Available Now: Linux VDA 7.15 LTSR!
    Originally, XenApp and XenDesktop releases occurred around once a year, similar to the Academy Awards, and contained significant updates. Many large enterprise customers needed to assess which version would be ideal to standardize their main production environment on for the coming years, unlike other customers seeking the latest features and capabilities who felt that the releases were not soon enough or feature requirements had changed over time.
  • [Video] YouTube screws us again and Linux is screwing itself.
    Google is up to their old tricks again.They have figured how to ripoff their content providers with a new ad algorithm. Meanwhile, Linux podcasting is a clown show and I'm sick of dealing with it.

Fedora: Fedora + Plasma + Unity, Design Interns, and New ISO Build

  • Fedora + Plasma + Unity = Nice looks?
    Hybrid things aren't usually the best option around. Like hybrid cars, for example. Technically, when you marry concepts, you change the energy state, and while this could make sense in that you blend the best of several worlds, when this is done in a forced manner over a short period of time rather than eons of evolution, you end with the worst bits as the product of your mutation. I read about the United theme for Plasma a few months ago, and given that I've spent a fair deal of time fiddling with themes and icons and fonts and making different desktop environments look prettier than their defaults, I was intrigued. So I decided to see whether the notion of having Plasma look like Unity is a sane option. Let us.  Fedora + Plasma + Unity = Nice looks? [...] What is thy point, Vanessa, the astute among you may ask? Well, I have nothing against United or its creators, but I did come to the conclusion that too much tweaking is worse than no tweaking, if this statement makes sense. I like the notion of trying to overcome the inherent problems in each desktop through the use of themes and extensions. After all, I've been doing that profusely for the past few months. But it gets undone when you cross the desktop environment space. Making Gnome better yes. Making Plasma better, absolutely. Unity as an overlay for Plasma, well tricky. There's too much disparity for you to be able to hide the underlying workflow mechanisms and UI philosophies. Then, every little inconsistency glares. You notice things you do not expect, and you get angry because there are certain things you do expect. Some transformations work quite well because they build on the foundations, e.g. various Gnome panels or Macbuntu. But Plasma has its own special charm and flow and making it into a weird version of Unity, which itself is a weird version of Gnome misses the bigger picture. And so, if you're asking me, Plasma and Unity are two separate worlds, best enjoyed in isolation. United is an interesting notion, but it also signifies the upper limit for my own wild ideas and tweaking. Yes, you can make it work, then again, it means taking away from the beauty and style of what these two desktops do, and that's not the purpose of my pimping guides. So we shall stop here, and explore other colors and shapes. Have fun, little penguins.
  • Fedora Design Interns 2017
    Here’s an update on internships. Older post linked to here. Quick recap: there’s been 2 long-term interns for Fedora design team since February, and one short-term guy, who came for 2 weeks at the beginning of June. Guys have been doing an amazing job, I can’t stress enough how happy I am to have them around.
  • F26-20170815 Updated ISOs released

today's howtos

Security: Hardware Back Doors, Microsoft Windows, Kronos

  • Hiding malware in boobytrapped replacement screens would undetectably compromise your mobile device
     

    On the one hand, if you let an untrusted stranger install hardware in your electronic device, you're opening yourself up to all kinds of potential mischief; on the other hand, an estimated one in five smartphones has a cracked screen and the easiest, most efficient and cheapest way to get that fixed is to go to your corner repair-shop.  

  • How hackers {sic} are targeting the shipping industry [iophk: "Microsoft TCO"]
     

    Whenever one of the firm's fuel suppliers would send an email asking for payment, the virus simply changed the text of the message before it was read, adding a different bank account number.  

  • Locky ransomware is back from the dead with two new strains [iophk: "Windows TCO"]
     

    What hasn't changed, though, is the method of distribution.Rather than rifling through the trove of spilt US National Security Agency exploits, as the groups behind WannaCry and NotPetya did, Locky is distributed via phishing emails containing malicious Microsoft Office files or zipped attachments containing a malicious script.

  • Connected cars could have an airbag problem
     

    "It's not the car manufacturers' fault, and it's not a problem introduced by them. The security issue that we leveraged in our research lies in the standard that specifies how the car device network (i.e., CAN) works," added Trend.

    [...] To eliminate the risk entirely, an updated CAN standard should be proposed, adopted, and implemented. This whole process would likely require another generation of vehicles."

  • Code chunk in Kronos malware used long before MalwareTech published it
    A chunk of code found in the Kronos bank-fraud malware originated more than six years before security researcher Marcus Hutchins is accused of developing the underlying code, a fellow security researcher said Friday. The conclusion, reached in an analysis of Kronos published by security firm Malwarebytes, by no means proves or disproves federal prosecutors' allegations that Hutchins wrote Kronos code and played a role in the sale of the malware. It does, however, clarify speculation over a Tweet from January 2015, in which MalwareTech—the online handle Hutchins used—complained that a complex piece of code he had published a month earlier had been added to an unnamed malware sample without his permission.
  • Secret chips in replacement parts can completely hijack your phone’s security
    People with cracked touch screens or similar smartphone maladies have a new headache to consider: the possibility the replacement parts installed by repair shops contain secret hardware that completely hijacks the security of the device. The concern arises from research that shows how replacement screens—one put into a Huawei Nexus 6P and the other into an LG G Pad 7.0—can be used to surreptitiously log keyboard input and patterns, install malicious apps, and take pictures and e-mail them to the attacker. The booby-trapped screens also exploited operating system vulnerabilities that bypassed key security protections built into the phones. The malicious parts cost less than $10 and could easily be mass-produced. Most chilling of all, to most people, the booby-trapped parts could be indistinguishable from legitimate ones, a trait that could leave many service technicians unaware of the maliciousness. There would be no sign of tampering unless someone with a background in hardware disassembled the repaired phone and inspected it.