Search Results: "ag"

9 July 2013

Raphaël Hertzog: My Free Software Activities in June 2013

This is my monthly summary of my free software related activities. If you re among the people who made a donation to support my work (106.39 , thanks everybody!), then you can learn how I spent your money. Otherwise it s just an interesting status update on my various projects. Debian France I handled some subscriptions that we collected during Solutions Linux at the end of last month and I also worked on updating the accounts in preparation of our annual general assembly. As the current president, I wrote a moral assessment of the organization and I helped Sylvestre Ledru (the treasurer) to prepare an overview of our financial situation (which is rather good). The plan for this general assembly included the renewal of 6 of our 9 board members so I tried to motivate some persons to candidate and I m pretty happy to see that we managed to have 9 candidates for 6 seats, a real election for once. :-) And as usual, I updated Galette to version 0.7.4.2 and I filed a couple of tickets (#621, #622). Debian Package Tracking System We re getting close to one month of work on the Google Summer of Code Project that rewrites the Package Tracking System. On average I spent a good 1h30 per day on reviewing the code, giving my feedback, and preparing the user stories for the next iteration, plus a 2 hour meeting each Wednesday afternoon. This is more than I expected but at I m rather happy with the result so far. We have a live test instance updated each week (after the end of the iteration) at pts.debian.net. The web interface is empty because the bulk of the work has been spent on the email interface for now, but it s now feature complete and already has seen some improvements compared to the current implementation (fixing #340863 for example). You can interact with it by sending mails to control@pts.debian.net. The Debian Administrator s Handbook The fundraising for the liberation of the original book in French met its initial target very quickly and we added new targets with supplementary rewards (more ebook from Eyrolles, donation to Debian). All the supplementary targets were met, although the last one took until the last day! Thanks to all the supporters, we now have a French translation of the Debian Administrator s Handbook which is free and we have collected about 2700 EUR for Debian. Debian Packaging I got a couple of release critical bug reports that I had to fix: And trying to anticipate future issues, I filed an upstream ticket on feed2omb (#33) to see whether upstream had plans to support the new pump.io API that identi.ca is supposed to use soonish. Kali Linux I filed a couple of Debian bugs: #711866 to request a new upstream version of w3af in Debian, #711044 to report a missing dependency in LSB meta-informations of the vsftpd init script. I worked on packaging passing-the-hash. Basically this is a fork of several software just to override some NTLM authentication functions. In some cases, I managed to avoid the fork by transforming the patches in LD_PRELOAD libraries that override the specific symbol of the patched functions. Among the forked software, there was winexe which wasn t packaged yet. So I packaged it but we quickly ran into some segfaults (which was already reported to upstream since a few months). I investigated the problem and prepared a patch. It has been submitted to upstream and merged. Thanks See you next month for a new summary of my activities.

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Raphael Geissert: Explaining segmentation fault errors

Want to fix that segfault you keep hitting or was reported to you? The first step is to understand the error message you get.

So you have a message like the following:
segfault at bfea3fec ip 080ee07e sp bfea3fa0 error 6

You might already know that ip means instruction pointer and sp means stack pointer and as such the addresses that follow them are the values in those registers. But what does the error number mean?

The error number, or code, actually gives you a better explanation of what the cause of the segfault is. The number's bits are flags describing the error and are architecture-dependent. For x86/x86_64 I just wrote an online converter/decoder that you can use to explain the segfault error code.

As an example, the above error code is explained as:
The cause was a user-mode write resulting in no page being found.

And the common error 4:
The cause was a user-mode read resulting in no page being found.
(also known as a null pointer dereference).

Enjoy.

Daniel Pocock: Enabling Elliptic Curve Cryptography in OpenWRT and strongSwan VPNs

OpenWRT currently ships an OpenSSL package with Elliptic Curve Cryptography (ECC) disabled. This is very inconvenient as ECC is now standard in other distributions like Debian and Ubuntu and it is necessary to solve certain problems such as making IPsec VPNs work reliably It is relatively easy to enable it, this also provides a useful opportunity to see how the OpenWRT build system works. Preparing the build environment The build was done on a Debian 7 (wheezy) workstation. It is necessary to install some packages that provide tools needed for the build: 
apt-get install gcc binutils flex make unzip gawk libz-dev linux-libc-dev
Rebuild the OpenSSL and StrongSwan packages This was tested with an ar71xx CPU-based router. You can easily change the config (run make menuconfig just before make defconfig) for other variations of router.
Running strongSwan IPsec on a router requires a router with plenty of flash, RAM and CPU power. Cheap routers with limited flash will not be able to install the packages at all. I tested on the Buffalo WZR-HP-AG300H-EU which has 32MB flash and 128MB RAM Here are the commands executed on the Debian build workstation: 
mkdir ~/ws
cd ~/ws
svn checkout svn://svn.openwrt.org/openwrt/trunk openwrt-trunk
cd openwrt-trunk
./scripts/feeds update -a
./scripts/feeds install -a
wget -O .config \
  http://danielpocock.com/sites/danielpocock.com/files/openwrt.config.txt
sed -i -e 's/no-ec//' package/libs/openssl/Makefile 
make defconfig
make -j 13
The "make" command will build all the packages. It takes some time. Copy the packages to a router The actual location of the packages in your source tree depends on the CPU architecture you chose to build for. You can find them with a command such as: 
find . -name '*.ipk'
Here we look at how to copy the packages for the ar71xx based router into the /tmp directory on the router. The router IP is 192.168.1.1 below: 
cd ./bin/ar71xx/packages/
scp libopenssl_1.0.1e-1_ar71xx.ipk strongswan*.ipk root@192.168.1.1:/tmp
Installing the packages It is relatively easy to install the packages using the opkg utility on OpenWRT. When using self-compiled packages, you are likely to get errors about the checksums. OpenWRT compares the checksum of the package to the checksum from the package catalog file. You can delete the catalog file (e.g. rm /var/opkg-lists/attitude_adjustment) and then opkg will install the package without complaining. The file is automatically placed there each time you run opkg update so there is no harm in deleting it. In my earlier blog, I looked at how to link Android clients to the strongSwan VPN. Unfortunately Android has a bug in ECC support too and must still be used with RSA certificates. Nonetheless, the OpenWRT VPN will be quite happy talking to Linux laptops and servers - you may need to rebuild OpenSSL and StrongSwan on any Fedora, Red Hat or CentOS systems that require ECC support too. As you migrate from RSA to ECC certificates it is quite feasible to have both types of certificates in use at the same time. strongSwan supports this type of hybrid environment. To make the migration to ECC go smoothly it is desirable to ensure all boxes have ECC support at the earliest opportunity.

8 July 2013

Olivier Berger: Experimenting with Linked Open Data about FLOSS projects : matching Debian upstream projects

I ve been experimenting with Linked Open Data about FLOSS projects harvested from different sources of DOAP or ADMS.SW descriptions. I ve tried and match upstream projects of Debian packages with upstream projects hosted at Apache, Gnome, or Alioth.debian.org, or catalogued on Pypi. I m matching them on identical values of the Homepage field (comparing the Homepage Control field set by Debian packagers with the doap:homepage meta-data in the RDF documents harvested from the upstream project catalogues). Here are initial results of my little experiment, for number of matched projects, and results on project name s similarity :
Upstream catalogue Total matching projs Exact same project name Same project name (case independant)
apache 31 0 (0 %) 0 (0 %)
alioth 16 13 (81 %) 13 (81 %)
pypi 439 217 (49 %) 273 (62 %)
gnome 21 0 (0 %) 7 (33 %)
Total 507 230 (45%) 293 (58 %)
The data set contains tens of thousands of projects, with probably many duplicates, but from all of these, only 507 have common homepages. As you can see, in some cases, the Debian source package names match the upstream project name (sometimes with lower/upper case variants), but in general, the project names aren t identical, so it is interesting to try and match them by homepage. For the curious ones, the Apache, Gnome and Pypi project catalogues use to provide RDF meta-data for quite some time. More recently have we introduced ADMS.SW meta-data for Debian source packages, and even more recently for the Alioth projects (through the ADMS.SW exporter plugin for FusionForge). There are still some ways for improvements, for instance to normalize homepage URLs which tend to vary (trailing slashes, or different HTTP/HTTPS schemes). Stay tuned for more details.

7 July 2013

Sylvain Beucler: Invitation to the GNU Hackers Meeting 2013

Here's a WebGL-powered invitation to the GNU Hackers Meeting 2013, which is taking place in Paris on August 22-25 :) http://www.beuc.net/demo-ghm/v1/ Free, hardware-accelerated WebGL support is recent under GNU/Linux, you'll need Mesa/Mesa-DRI 9 and Linux kernel 3.6 from Debian sid plus a recent Firefox, though a Mesa-software fallback is usually available in earlier versions. Meanwhile, here's a WebM capture: <video controls="true" src="http://www.beuc.net/demo-ghm/v1/sylvain/output.webm"> Your browser doesn't support WebM video or you've disabled GIF images </video> (Curious about the capture process?) Work is underway on an extended version of this invitation/demo, peek here :) http://www.beuc.net/demo-ghm/v2/

Sylvestre Ledru: LLVM toolchain packages

In parallel of my work on the LLVM Debian/Ubuntu nightly packages, I uploaded a couple months ago the same packages for the stable releases of the LLVM toolchain. By toolchain, this means LLVM + Clang + Clang extra tools + compiler-rt + polly + LLDB.
Previously, they were packaged as separate source packages. Making the maintenance harder and, especially, limiting the packaging of LLDB and polly. Currently, we have in the archive: For the 3.2 release, I am planning to focus on RC bug fixes.
The 3.3 and snapshot releases will get the feature improvements.
llvm-default will point to the 3.3 release once it builds on all architectures and it reached testing aka Jessie (probably during summer).
Original post blogged on b2evolution.

Gregor Herrmann: RC bugs 2013/26-27

not that we have a lack of RC bugs; still, I was a bit lazy in the last two weeks. here's what I've worked on:

Raphael Geissert: Dealing with bashisms in proprietary software

Sometimes it happens that for one reason or another there's a need to use a proprietary application (read: can not be modified due to its licence) that contains bashisms. Since the application can not be modified and it might not be desirable to change the default /bin/sh, dealing with such applications can be a pain. Or not.

The switchsh program (available in Debian) by Marco d'Itri can be used to execute said application under a namespace where bash is bind-mounted on /bin/sh. The result:

$ sh --help
sh: Illegal option --
$ switchsh sh --help   head -n1
GNU bash, version 4.1.5(1)-release-(i486-pc-linux-gnu)

Simple, yet handy.

Daniel Pocock: Melbourne and Detroit emergency call centers simultaneously fail

A co-incidence that caught my eye this week was the failure of emergency call centers in Melbourne, Australia and Detroit, USA. Melbourne's system failed at 19:00 local time on Friday, 5 July. Detroit's communications meltdown started at 05:00 local time on the same day. 19:00 - 05:00 = 14:00 hours, which is, co-incidentally, the difference in timezones between the two cities Detroit's failure was slashdotted, Melbourne's was not. Were there other cities that experienced this same outage on Friday? Just what could be going on then? Are they running their systems on a common cloud infrastructure that is not completely under the control of local technical staff? Was there an expired SSL certificate embedded in the application software, much like the certificate expiry that recently caused failure in Microsoft Azure? Using free and open source software is a life or death issue Are these systems based on free and open source software? Can the local authorities, their technical experts and auditors inspect the software to detect such issues ahead of time? Closed, proprietary outsourced solutions often take significant control away from the users of technology.

Paul Tagliamonte: Hy 0.9.10 released

A huge release, the combined 0.9.9 and 0.9.10 releases (I made a mistake releasing) are now tagged and pushed to pypi. It features a number of enhancements and fixes, and is just an absolute thrill to play with. Thanks to the contributors this cycle:
Bob Tolbert Christopher Allan Webber Duncan McGreggor Guillermo Vaya Joe H. Rahme Julien Danjou Konrad Hinsen Morten Linderud Nicolas Dandrimont Ralph Moritz rogererens Thomas Ballinger Tuukka Turto
Outstanding! New features are now being considered for 0.9.11. Thanks!

6 July 2013

Sylvestre Ledru: Automatic scan-build on the LLVM toolchain

After setting an automatic code coverage tool, I just plugged an automatic scan-build on the LLVM toolchain trunk: http://buildd-clang.debian.net/scan-build/ Note that: This work is done through the Debian/LLVM jenkins instance.
The report is updated twice a day.
The scan-build/clang used to produce the report is the one published on http://llvm.org/apt/. That means that a new feature/fix done on scan-build will appear only about a day after on report. As a side effect, it tests automatically the packages distributed on llvm.org/apt/. For a project of this size, the number of reported errors / warnings is pretty low. At time of writing, only 329 errors are reported and many of them are in generated code (AttrDump.inc and LLDBWrapPython.cpp for example) or in unit tests. [1]
/tmp/buildd/llvm-toolchain-snapshot-3.4~svn185728/build-llvm/Release/bin/clang -fno-exceptions -fPIC -funwind-tables -I/tmp/buildd/llvm-toolchain-snapshot-3.4~svn185728/projects/compiler-rt/lib -I/tmp/buildd/llvm-toolchain-snapshot-3.4~svn185728/projects/compiler-rt/include -Wall -Werror -O3 -fomit-frame-pointer -m64 -fPIE -fno-builtin -gline-tables-only -fno-rtti -DASAN_FLEXIBLE_MAPPING_AND_OFFSET=1 -c -o /tmp/buildd/llvm-toolchain-snapshot-3.4~svn185728/build-llvm/tools/clang/runtime/compiler-rt/clang_linux/asan-x86_64/x86_64/SubDir.lib__sanitizer_common/sanitizer_symbolizer_itanium.o /tmp/buildd/llvm-toolchain-snapshot-3.4~svn185728/projects/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_itanium.cc
Original post blogged on b2evolution.

Steve Kemp: This weekend I will be mostly upgrading to wheezy

Having migrated my websites away from my ssh/mail box I'm going to upgrade that this weekend. I've got my new mail client, lumail, working well enough to use exclusively, so the upgrade should be nice and simple. I spent a few hours last night removing packages from my ssh/mail box to trim it down. Removing a bunch of Perl modules I used in my CGI coding, removing services such as nfs-common, portmapper, etc. Today I'll have a stab at the upgrade. The only thing I have to be careful of is my backported/tweaked qpsmptd packages. I'll try the native wheezy version now it has caught up. (I don't use any of the standard qpsmtpd plugins at all. Instead I have a separate tree of my own custom anti-spam and virtual-hosting aware plugins. They all work in a unified fashion. Using these plugins against a new version of qpsmtpd should be just fine. But obviously I need to test that.) Work on Lumail is probably going to slow down now it is genuinely in use, but I'll keep an eye out for feature requests and missing primitives. Annoyingly I wasted 30 minutes just now implementing a plugin I'd already written: lumail issue #51. I also need to step-back this weekend and reassess my hosting. When I was tweaking my slaughter setup I recently realized I have more hosts than I thought: Total: 13 virtual machines. (+ one kvm-host)

Yves-Alexis Perez: Xfce 4.10, final part

Someone recently asked me about the Debian Xfce 4.10 status, as apparently I forgot to update this post series. So, as you might have noticed, the full Xfce 4.10 desktop environment is currently in Debian Jessie (current name for testing). All in all, the transition went well and smooth. One of the most regular question I get about Xfce 4.10 is the panel behavior when it comes to the task bar expansion. In xfce4-panel 4.8, when people wanted to have a full side panel with a task bar plugin inside, they added a Windows buttons plugin and configured the panel to 100% length. Then the Windows buttons would expand to occupy all the free space on the panel. It was a special case plugins, as usually other plugins only used a fixed space. Now, in 4.10, this is not the case anymore. Windows button uses a fixed size. And the plugins are left-aligned, which means usually people end up with some space at the far right of the panel. To restore the previous behavior back (which is actually the pre-4.8 behavior, 4.8 was an exception by itself), one needs to add a Separator plugin, then configure it to expand (and optionnally select a transparent handle). Then move it next right to the Windows buttons plugin. Another thing which might be a bit surprising for upgrading users is the change in the Action buttons plugin, which people usually use to logout. In 4.8, by default, it's set to run the logout dialog. In 4.10, by default, it's set to logout directly (but with a confirmation dialog). If you prefer the previous behavior, you can just configure the Action buttons plugin and select the Log out item instead of the Log out one (I know, it's a bit confusing). If you have any question, don't hesitate to reach us by mail or on irc (#debian-xfce on Freenode). Other than that remember that Xfce really needs you help, both in Debian and upstream (and at that point, I'd say *especially* upstream). There's a lot of unmaintained project under the Xfce umbrella, some of them part of the core (like xfce4-power-manager), so if you have some spare time and some C/GTK+ knowledge, feel free to contact the Xfce team on the mailing list.

5 July 2013

Niels Thykier: Dealing with a bottleneck, wasted inodes and reducing memory usage

We finally managed to deal with one of the major runtime bottlenecks in Lintian. Previously, our usage of file(1) would sometimes spend a long time classifying various text files. In Lintian 2.5.14, we applied a series of patches that allowed us to disable file(1) s ascii test. This means that Lintian will now see all text files as data , which is somewhat uninformative. However, it turns 
N: [...] file-info for source:linux/3.2.20-1 done (120.350s)
into 
N: [...] file-info for source:linux/3.2.20-1 done (20.984s)
In the same version, we also had Lintian create fewer empty files and directories in its laboratory. For the normal user, this change has hardly any practical effect. But for lintian.d.o, this reduces the minimum inodes consumed for binary entries with 8 or so. For Lintian 2.5.15, we have may end up reducing the memory requirements of Lintian a bit. So far, we got two changes applied that is taking out at least 12MB of RAM usage on the linux source package and 21 of its binaries. Furthermore, Lintian will (if Devel::Size is available) be able to tell how much memory it is using for its caches when run with -dddd .

Daniel Leidert: Dear Lazyweb ... why does lshw (still) identify my Linux raid autodetect partition(s) as NTFS volumes?

In a very first attempt, my disk:2 was partitioned and initialized as follows:
/dev/sdc1     1,5TB     NTFS
/dev/sdc2     0,5TB     EXT4
This was later changed to what you can see below and what fdisk correctly reports. These partitions all use the EXT4 file system.
[..]
   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048   524290047   262144000   fd  Linux raid autodetect
/dev/sdb2       524290048  3907029167  1691369560   fd  Linux raid autodetect
[..]
   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1            2048   524290047   262144000   fd  Linux raid autodetect
/dev/sdc2       524290048  3907029167  1691369560   fd  Linux raid autodetect
[..]
I'm wondering why lshw and parted shows some of the partitions still being NTFS volumes? Checkout the output below. How can this be fixed? What is missing? Erase some header data?

Model: ATA WDC WD20EFRX-68A (scsi)
Disk /dev/sdb: 2000GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos

Number  Start   End     Size    Type     File system  Flags
 1      1049kB  268GB   268GB   primary               raid
 2      268GB   2000GB  1732GB  primary               raid


Model: ATA WDC WD20EFRX-68A (scsi)
Disk /dev/sdc: 2000GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos

Number  Start   End     Size    Type     File system  Flags
 1      1049kB  268GB   268GB   primary  ntfs         raid
 2      268GB   2000GB  1732GB  primary               raid
[..]
  *-disk:1
       description: ATA Disk
       product: WDC WD20EFRX-68A
       vendor: Western Digital
       physical id: 1
       bus info: scsi@3:0.0.0
       logical name: /dev/sdb
       version: 80.0
       serial: WD-WCC300354221
       size: 1863GiB (2TB)
       capabilities: partitioned partitioned:dos
       configuration: ansiversion=5 sectorsize=4096
     *-volume:0
          description: Linux raid autodetect partition
          physical id: 1
          bus info: scsi@3:0.0.0,1
          logical name: /dev/sdb1
          capacity: 250GiB
          capabilities: primary multi
     *-volume:1
          description: Linux raid autodetect partition
          physical id: 2
          bus info: scsi@3:0.0.0,2
          logical name: /dev/sdb2
          capacity: 1613GiB
          capabilities: primary multi
  *-disk:2
       description: ATA Disk
       product: WDC WD20EFRX-68A
       vendor: Western Digital
       physical id: 2
       bus info: scsi@4:0.0.0
       logical name: /dev/sdc
       version: 80.0
       serial: WD-WCC1T0567095
       size: 1863GiB (2TB)
       capabilities: partitioned partitioned:dos
       configuration: ansiversion=5 sectorsize=4096 signature=000a4d07
     *-volume:0
          description: Windows NTFS volume
          physical id: 1
          bus info: scsi@4:0.0.0,1
          logical name: /dev/sdc1
          version: 3.1
          serial: 013e-8473
          size: 1396GiB
          capabilities: primary multi ntfs initialized
          configuration: clustersize=4096 created=2013-06-18 06:24:11 filesystem=ntfs label=MEDIA state=clean
     *-volume:1
          description: Linux raid autodetect partition
          physical id: 2
          bus info: scsi@4:0.0.0,2
          logical name: /dev/sdc2
          capacity: 1613GiB
          capabilities: primary multi
[..]

Francesca Ciceri: #debcraft: DIY projects to show your Debian love

The next August 16th, Debian will turn 20.
What are you planning to do to to celebrate?
Being a DIY geek, I decided to create some craft projects dedicated to the Universal Operating System. I'll publish them, one per week, on this blog with a detailed tutorial, released under a CC:BY-SA 3.0 license. If you have an original project dedicated to Debian (from cookies and cakes to knitted socks, from beaded earrings to handpainted mugs, from plushies to pottery, from glass arts to lettering and so on) join me!
Post a tutorial about your project on your blog (or if you don't have one, send me a mail and you'll publish it here as guest post) with the hashtag #debcraft and a free (as in freedom) license. Bonus points for project using recycled material :). Ready to start? Below my first one: swirl charms from plastic bottles.
please, do try this at home a couple of finished swirl This is a little tutorial on how to create swirl charms for keyrings from plastic bottles.
The project is really easy and quick to realize, the materials very common and the result quite pretty.
I found out that there are tons of tutorial in the Internet about how to make jewelry from PET bottles, and I'll surely give them a try (earrings, in particular, seem a good idea).
If you want some inspiration, I suggest you to check out the amazing work of Turkish artist Gulnur Ozdaglar who creates ethereal jewelry and everyday objects from plastic bottles.
"What is PET bottle?
A domesticated bottle kept for companionship or amusement."
Gulnur Ozdaglar
What you will need tools and materials needed In the pic there's also a soda can, because I thought it could be a good material too.
After some tests, I decided that soda cans would probably need some resin to make the edges less sharp and avoid cuts, so I think I'll experiment a bit more with them. Step 1 step 1: cut the swirl from plastic First of all, you'll need to cut out the swirl from the bottle.
I cut it in the upper part of the bottle, using a paper swirl as guide to cut the swirl shape as regular as I could. Step 2 step 2: melt the edges As the edges of the cut are a bit raw, I decided to lightly melt them with the lighter: be careful as if the plastic melt too much it will ruin our nice swirl. Also, remember to open a window while doing it: it's not a lot of melting but better safe than sorry. Step 3 step 3: punch a hole for the jumpring With a pin or a needle punch a hole in the upper part of the swirl, where the jumpring will be set to connect the swirl with the keychain ring. Now you need to decide which type of swirl do: for the painted one, follow step 4a; for the transparent one with the red embroidery, follow step 4b. Step 4a step 4a: paint the swirl Paint your swirl red, or of your favourite colour (I experimented a bit here, having lots of nail polish, and made also a purple one). Step 4b step 4b: punch more holes and sew with red thread With a pin or a needle, punch a series of holes, in the middle of the swirl, following the swirl shape.
Then embroider it using backstitch. Step 5 step 5: add the jumpring Add the jumpring, if you have a ready made one.
If not, use a pair of cutters to cut a little bit of metal wire and the pliers to create a ring with it, insert in the hole and close it. Step 6 step 6: add the metal keyring Connect the jumpring and the metal keyring. Congratulations: you now have a swirl shaped keycharm!

Justus Winter: mount, umount and mtab

This week was all about getting mount into shape, addind umount and hacking up a prototype for the mtab issue. With all my patches to mount the boot log looks like this: 
INIT: version 2.88 booting
Using makefile-style concurrent boot in runlevel S.
Activating swap...done.
Checking root file system...fsck from util-linux 2.20.1
hd2 : tray open or drive not ready
hd2 : tray open or drive not ready
hd2 : tray open or drive not ready
hd2 : tray open or drive not ready
end_request: I/O error, dev 02:00, sector 0
ext2fs_check_if_mount: Can't check if filesystem is mounted due to missing mtab file while determining whether /dev/hd0s1 is mounted.
/dev/hd0s1: clean, 44101/181056 files, 283413/723200 blocks
done.
Cleaning up temporary files... /tmp.
/etc/rcS.d/S06mtab.sh: 48: /etc/rcS.d/S06mtab.sh: cannot open /proc/mounts: No such file
Activating lvm and md swap...(default pager): Already paging to partition hd0s5!
done.
Checking file systems...fsck from util-linux 2.20.1
hd2 : tray open or drive not ready
hd2 : tray open or drive not ready
end_request: I/O error, dev 02:00, sector 0
done.
Mounting local filesystems...done.
Activating swapfile swap...(default pager): Already paging to partition hd0s5!
done.
df: Warning: cannot read table of mounted file systems: No such file or directory
Cleaning up temporary files....
Configuring network interfaces...inetutils-ifconfig: invalid arguments
ifup: failed to open pid file /run/network/ifup-/dev/eth0.pid: No such file or directory
Internet Systems Consortium DHCP Client 4.2.2
Copyright 2004-2011 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/
can't create /var/lib/dhcp/dhclient./dev/eth0.leases: No such file or directory
Listening on Socket//dev/eth0
Sending on   Socket//dev/eth0
DHCPDISCOVER on /dev/eth0 to 255.255.255.255 port 67 interval 7
DHCPREQUEST on /dev/eth0 to 255.255.255.255 port 67
DHCPOFFER from 10.0.2.2
DHCPACK from 10.0.2.2
can't create /var/lib/dhcp/dhclient./dev/eth0.leases: No such file or directory
bound to 10.0.2.15 -- renewal in 42107 seconds.
done.
Cleaning up temporary files....
Setting up X socket directories... /tmp/.X11-unix /tmp/.ICE-unix.
INIT: Entering runlevel: 2
Using makefile-style concurrent boot in runlevel 2.
Starting enhanced syslogd: rsyslogd.
Starting deferred execution scheduler: atd.
Starting periodic command scheduler: cron.
Starting system message bus: dbusFailed to set socket option"/var/run/dbus/system_bus_socket": Protocol not available.
Starting OpenBSD Secure Shell server: sshd.
GNU 0.3 (debian) (console)
login:
As you can see, mountall.sh works fine now (it's the line about mounting local filesystems). This is a list of issues I tackled this week: Note that even though I've implemented umount, it doesn't actually work yet. That is because umount needs a mtab file or /proc/mounts to do anything, because you can either invoke umount with the mount point or the device and umount needs an mtab style file to figure out whether the argument is referring to the former or the latter. So the next big issue is the mtab issue. There is some information about that in the Hurd wiki, it even is a gsoc project idea of its own: http://www.gnu.org/software/hurd/community/gsoc/project_ideas/mtab.html But I need this now, this cannot wait for another gsoc. The implementation outlined by that page consists roughly of: If this hypothetical mtab translator is bound to say /proc/mounts this would solve all our problems: 
% settrans -ca /proc/mounts /hurd/mtab /
As this involves adding a RPC procedure and keeping a list of passive and active translators, this involves some design decisions. As discussed in #hurd I hacked up a prototype and post it for review: http://lists.gnu.org/archive/html/bug-hurd/2013-07/msg00022.html As soon as I get the necessary feedback on this issue, I will get the implementation up to speed. Until then, I will pick another item from my status list, most probably the ifupdown issue. Speaking of feedback, all of my patches I sent last week were merged at the appropriate locations. That was really quick, many thanks for that :) While working on the mount issues, I frequently looked at the implementation of Linux' and FreeBSD's mount to see how --types is handled there. I must admit that I was not to keen about the idea of writing c again, but I was positively surprised by the code I've seen from Hurd so far. As Hurd is the operating system of the GNU system, its code is free to use any GNU extension to libc and gcc including nice stuff like nested functions. If you look at the different mount implementations, you'll find the Hurd version to be the most modern and clean one imho:
Linux
http://sources.debian.net/src/util-linux/2.20.1-5.4/mount/mount.c
FreeBSD
http://sources.debian.net/src/freebsd-utils/9.0%2Bds1-11/sbin/mount/mount.c
Hurd
http://sources.debian.net/src/hurd/20130620-1/utils/mount.c
See you next week :)

EvolvisForge blog: Send Alt-SysRq-* to virt-manager guest using virsh

virsh send-key guestname KEY_LEFTALT KEY_SYSRQ KEY_H This doesn t work in virt-manager, but the virsh CLI tool is just fine. PS: zerofree rocks! And can be installed in Grml 2011.05 just finely.

Petter Reinholdtsen: The Thinkpad is dead, long live the Thinkpad X230?

Half a year ago, I reported that I had to find a replacement for my trusty old Thinkpad X41. Unfortunately I did not have much time to spend on it, and it took a while to find a model I believe will do the job, but two days ago the replacement finally arrived. I ended up picking a Thinkpad X230 with SSD disk (NZDAJMN). I first test installed Debian Edu Wheezy as a roaming workstation, and it seemed to work flawlessly. But my second installation with encrypted disk was not as successful. More on that below. I had a hard time trying to track down a good laptop, as my most important requirements (robust and with a good keyboard) are never listed in the feature list. But I did get good help from the search feature at Prisjakt, which allowed me to limit the list of interesting laptops based on my other requirements. A bit surprising that SSD disk are not disks according to that search interface, so I had to drop specifying the number of disks from my search parameters. I also asked around among friends to get their impression on keyboards and robustness. So the new laptop arrived, and it is quite a lot wider than the X41. I am not quite convinced about the keyboard, as it is significantly wider than my old keyboard, and I have to stretch my hand a lot more to reach the edges. But the key response is fairly good and the individual key shape is fairly easy to handle, so I hope I will get used to it. My old X40 was starting to fail, and I really needed a new laptop now. :) Turning off the touch pad was simple. All it took was a quick visit to the BIOS during boot it disable it. But there is a fatal problem with the laptop. The 180 GB SSD disk lock up during load. And this happen when installing Debian Wheezy with encrypted disk, while the disk is being filled with random data. I also tested to install Ubuntu Raring, and it happen there too if I reenable the code to fill the disk with random data (it is disabled by default in Ubuntu). And the bug with is already known. It was reported to Debian as BTS report #691427 2012-10-25 (journal commit I/O error on brand-new Thinkpad T430s ext4 on lvm on SSD). It is also reported to the Linux kernel developers as Kernel bugzilla report #51861 2012-12-20 (Intel SSD 520 stops working under load (SSDSC2BW180A3L in Lenovo ThinkPad T430s)). It is also reported on the Lenovo forums, both for T430 2012-11-10 and for X230 03-20-2013. The problem do not only affect installation. The reports state that the disk lock up during use if many writes are done on the disk, so it is much no use to work around the installation problem and end up with a computer that can lock up at any moment. There is even a small C program available that will lock up the hard drive after running a few minutes by writing to a file. I've contacted my supplier and asked how to handle this, and after contacting PCHELP Norway (request 01D1FDP) which handle support requests for Lenovo, his first suggestion was to upgrade the disk firmware. Unfortunately there is no newer firmware available from Lenovo, as my disk already have the most recent one (version LF1i). I hope to hear more from him today and hope the problem can be fixed. :)

4 July 2013

Emanuele Rocca: Useful tools for Python developers

Python is a great language with an impressive number of tools designed to make developers' life easier. Sometimes, however, the problem is getting to know that these tools exist in the first place. By contributing to projects like OpenStack's Nova client and Falcon, I have recently come across some useful tools that can seriously improve the quality of your code. The first one is called pyflakes, a passive checker of Python programs developed by Phil Frost. What it does is parsing your source files and checking for possible errors such as undefined names and unused imports. Let's consider the following example: <figure class="code">
1
2
3
4

import urllib

print "pyflakes example"
urlib.urlopen('http://www.linux.it')
</figure>The code above contains a typo, we have misspelled urllib. Here is what pyflakes thinks about our program: 
$ pyflakes example.py
example.py:1: 'urllib' imported but unused
example.py:4: undefined name 'urlib'
On line 4 we try to use urlib which is not defined. Also, we import urllib on line 1 and we do nothing with it. Our typo has been spotted! Notice that, even though our program contains a print statement, 'pyflakes example' has not been printed. That is because pyflakes parses the source files it checks, without importing them, making it safe to use on modules with side effects. pyflakes can be installed with pip or apt-get. The second tool I want to talk about is Ned Batchelder's coverage.py. No doubt you write unit tests for your programs. Right? Good. coverage.py is out there to help you checking how much of your program is actually covered. Let's use as an example codicefiscale, a Python project of mine. First we install coverage: 
pip install coverage
Then we run our unit tests: 
$ coverage run --source=codicefiscale tests.py
.......
----------------------------------------------------------------------
Ran 7 tests in 0.003s
We pass the module we want to test with --source=codicefiscale so that coverage will only report information about that specific module. Now that our tests have been performed successfully it is time to check how much of our code is covered by unit tests: 
$ coverage report -m
Name            Stmts   Miss  Cover   Missing
---------------------------------------------
codicefiscale      73      4    95%   61, 67, 95, 100
Not bad, 95% of our module is covered! Still, coverage let us know that 4 lines have not been touched by the unit tests. With this information, we can go write some meaningful test cases that will also cover the missing lines.

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