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Pi and BeagleBone for Dummies in library
by Ian Young 22 Jun '15

22 Jun '15

City libraries have titles in the Dummies series about the Raspberry Pi and BeagleBone. Much of the material is directed at providing information on Linux for beginners, covering much the same ground in both titles. There is also a primer on Python programming. Perhaps the most interesting information deals with hardware aspects of interfacing with the boards including several small projects. In related news the latest Distrowatch Weekly has an article on using a Raspberry Pi as a server for backups in a home network.

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Resurrecting The SuperH Architecture
by Lawrence D'Oliveiro 18 Jun '15

18 Jun '15

I guess this is more of an embedded thing, but ... <http://lwn.net/Articles/647636/> “He then asked what constitutes the minimal system that can run Linux. All that is really needed, he said, is a flat, 32-bit memory address space, a CPU with registers to hold instructions, some I/O and storage (from which the kernel and initramfs can be loaded), and a timer for interrupts. That plus GCC is sufficient to get Linux running—although it may not be fast, depending on the specifics. One does not even need a cache, floating-point unit, SMP, or a memory-management unit (MMU).” “The other main advantage of the J2 project is that the work for implementing SuperH support is already done in the kernel, GCC, GDB, strace, and most other system components.” “The project has thus "inherited" an excellent ISA, and has even been in contact with many of the former Hitachi employees that worked on SuperH.” “...there are many ASIC vendors who are happy to produce low-cost chips on their older equipment because the cost of retooling a plant is exorbitant. A 180nm implementation of the J2 design, he said, costs around three cents per chip, with no royalties required. "That's disposable computing at the 'free toy inside' level."” “At the end of the talk, an audience member voiced concern that SuperH was old enough that support for it is unmaintained in a lot of projects. He suggested that the J2 team might need to act quickly to stop its removal. Landley noted that, indeed, the latest buildroot release did remove SuperH support, "but we're trying to get them to put it back now."”

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The South Pole Is On NZ Time!
by Lawrence D'Oliveiro 17 Jun '15

17 Jun '15

ldo(a)theon:~> ls -l /usr/share/zoneinfo/Antarctica/ ... lrwxrwxrwx 1 root root 5 Apr 27 10:36 South_Pole -> ../NZ ...

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Re: [wlug] The Fate Of The Fairfield Lab
by David Nicholls 17 Jun '15

17 Jun '15

So... What exactly is the Fairfield Lab? Where is it set up? a few details to elaborate on it's background might be helpful. I know someone with teaching (primary) and tech quals who might be useful. On 15 June 2015 at 11:56, Lawrence D'Oliveiro <ldo(a)geek-central.gen.nz> wrote: > To bring up a (not entirely) unrelated subject, I was at Te Whare O Te > Ata last week, and I asked Mike Rarere what was going to happen to the > computer lab. > > It’s clear Bruce Kingsbury was instrumental in getting this lab set up > and running, and it was providing a useful service to the community. > All of which was shot completely to hell as a result of his criminality > and stupidity. > > I understood from Mike that, without somebody willing to provide > full-time support for free, as Bruce was, the lab cannot continue. This > seems a shame, but is there anything else we can do? Fundraise to pay > someone to provide support, even if only part-time? > _______________________________________________ > wlug mailing list | wlug(a)list.waikato.ac.nz > Unsubscribe: http://list.waikato.ac.nz/mailman/listinfo/wlug > -- *Cheers...David Nicholls* *Computer Support* *Faculty of Science and Engineering* *x5006, *fsen_csg(a)waikato.ac.nz

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Fwd: [NZLUG] Major Ubuntu Linux Vulnerability - all current versions
by Peter Reutemann 16 Jun '15

16 Jun '15

Apologies, if you've already received this. Cheers, Peter ---------- Forwarded message ---------- From: Mark Foster Date: Wed, Jun 17, 2015 at 11:28 AM Subject: [NZLUG] Major Ubuntu Linux Vulnerability - all current versions To: NZ Linux Users Group <nzlug(a)lists.nzoss.org.nz>, aucklug(a)googlegroups.com, Wellington Linux Users Group <wellylug(a)lists.wellylug.org.nz> http://seclists.org/oss-sec/2015/q2/717 ... "allows a local root privilege escalation in the default configuration on all currently supported versions of Ubuntu. The overlayfs filesystem does not correctly check file permissions when creating new files in the upper filesystem directory. This can be exploited by an unprivileged process in kernels with CONFIG_USER_NS=y and where overlayfs has the FS_USERNS_MOUNT flag, which allows the mounting of overlayfs inside unprivileged mount namespaces. This is the default configuration of Ubuntu 12.04, 14.04, 14.10, and 15.04 [1]." This could be something requiring a bit of attention. Heads-up. There is a simple work-round if you're not using overlayfs, detailed at the above url. Mark. PS: Apol's for the cross-post. _______________________________________________ NZLUG mailing list NZLUG(a)lists.nzoss.org.nz http://lists.nzoss.org.nz/mailman/listinfo/nzlug -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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Linus Torvalds Says Linux Can Move On Without Him
by Peter Reutemann 16 Jun '15

16 Jun '15

'In a typically blunt interview, Linus Torvalds has said for the first time that if he were to die, Linux could safely continue on its own. Bloomberg has the report, which includes a video with Torvalds at his home office. Torvalds insists that people like Greg Kroah-Hartman have taken over huge parts of the day-to-day work maintaining Linux and that they've built up enough trust to be respected. This all comes as Torvalds has been irking more and more people with his aggressive attitude.' -- source: http://linux.slashdot.org/story/15/06/16/1630252 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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TRIM and Linux: Tread Cautiously, and Keep Backups Handy
by Peter Reutemann 16 Jun '15

16 Jun '15

'Algolia is a buzzword-compliant ("Hosted Search API that delivers instant and relevant results") start-up that uses a lot of open-source software (including various strains of Linux) and a lot of solid-state disk, and as such sometimes runs into problems with each of these. Their blog this week features a fascinating look at troubles that they faced with ext4 filesystems mysteriously flipping to read-only mode: not such a good thing for machines processing a search index, not just dishing it out. "The NGINX daemon serving all the HTTP(S) communication of our API was up and ready to serve the search queries but the indexing process crashed. Since the indexing process is guarded by supervise, crashing in a loop would have been understandable but a complete crash was not. As it turned out the filesystem was in a read-only mode. All right, let's assume it was a cosmic ray :) The filesystem got fixed, files were restored from another healthy server and everything looked fine again. The next day another server ended with filesystem in read-only, two hours after another one and then next hour another one. Something was going on. After restoring the filesystem and the files, it was time for serious analysis since this was not a one time thing. The rest of the story explains how they isolated the problem and worked around it; it turns out that the culprit was TRIM, or rather TRIM's interaction with certain SSDs: "The system was issuing a TRIM to erase empty blocks, the command got misinterpreted by the drive and the controller erased blocks it was not supposed to. Therefore our files ended-up with 512 bytes of zeroes, files smaller than 512 bytes were completely zeroed. When we were lucky enough, the misbehaving TRIM hit the super-block of the filesystem and caused a corruption." Since SSDs are becoming the norm outside the data center as well as within, some of the problems that their analysis exposed for one company probably would be good to test for elsewhere. One upshot: "As a result, we informed our server provider about the affected SSDs and they informed the manufacturer. Our new deployments were switched to different SSD drives and we don't recommend anyone to use any SSD that is anyhow mentioned in a bad way by the Linux kernel."' -- source: http://linux.slashdot.org/story/15/06/16/201217 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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meeting next Monday
by Peter Reutemann 16 Jun '15

16 Jun '15

Hi everyone We have a WLUG meeting coming up next Monday. Please note, that this is a social event taken place at The Cook and *not* at university as usual (the room wasn't available due to exams)! Details can be found here: http://www.meetup.com/WaikatoLinuxUsersGroup/events/222855181/ Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 http://www.cms.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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computer lab Te Whare O Te Ata
by Bill Rosoman 16 Jun '15

16 Jun '15

fyi I have been working many voluntary hours at Te Whare with mike for several months restoring, improving, documenting, training and assisting Mike to get things back to normal with the computers and the websites. So a lot of documentation has been happening. I do not think it is a good idea to see Mike and try and reopen the lab at this time after such an horrific experience they have been thru. They need time to see what the future holds for them. Bill Rosoman

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Re: [wlug] The Fate Of The Fairfield Lab
by William Mckee 15 Jun '15

15 Jun '15

I have the time and knowledge to open the lab. I've emailed Mike regarding this but recieved no reply. Rod has expressed interest in help running also. I'm willing to open the lab twice a week from 9-12. With more people I would love to open it from 2:30 till 5pm for primary and intermediate. It's a great resource and it makes me sad to see it closed. Cheers, William Cheers, On 15/06/2015 11:56 AM, "Lawrence D'Oliveiro" <ldo(a)geek-central.gen.nz> wrote: > To bring up a (not entirely) unrelated subject, I was at Te Whare O Te > Ata last week, and I asked Mike Rarere what was going to happen to the > computer lab. > > It’s clear Bruce Kingsbury was instrumental in getting this lab set up > and running, and it was providing a useful service to the community. > All of which was shot completely to hell as a result of his criminality > and stupidity. > > I understood from Mike that, without somebody willing to provide > full-time support for free, as Bruce was, the lab cannot continue. This > seems a shame, but is there anything else we can do? Fundraise to pay > someone to provide support, even if only part-time? > _______________________________________________ > wlug mailing list | wlug(a)list.waikato.ac.nz > Unsubscribe: http://list.waikato.ac.nz/mailman/listinfo/wlug >

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