Search Results: "tar"

22 July 2014

Neil Williams: Validating ARMMP device tree blobs

I ve done various bits with ARMMP and LAVA on this blog already, usually waiting until I ve got all the issues ironed out before writing it up. However, this time I m just going to do a dump of where it s at, how it works and what can be done. I m aware that LAVA can seem mysterious at first, the package description has improved enormously recently, thanks to exposure in Debian: LAVA is a continuous integration system for deploying operating systems onto physical and virtual hardware for running tests. Tests can be simple boot testing, bootloader testing and system level testing, although extra hardware may be required for some system tests. Results are tracked over time and data can be exported for further analysis. The LAVA documentation has a glossary of terms like result bundle and all the documentation is also available in the lava-server-doc package. The goal is to validate the dtbs built for the Debian ARMMP kernel. One of the most accessible ways to get the ARMMP kernel onto a board for testing is tftp using the Debian daily DI builds. Actually using the DI initrd can come later, once I ve got a complete preseed config so that the entire install can be automated. (There are some things to sort out in LAVA too before a full install can be deployed and booted but those are at an early stage.) It s enough at first to download the vmlinuz which is common to all ARMMP deployments, supply the relevant dtb, partner those with a minimal initrd and see if the board boots. The first change comes when this process is compared to how boards are commonly tested in LAVA with a zImage or uImage and all/most of the modules already built in. Packaged kernels won t necessarily raise a network interface or see the filesystem without modules, so the first step is to extend a minimal initramfs to include the armmp modules. 
apt install pax u-boot-tools
The minimal initramfs I selected is one often used within LAVA: 
wget http://images.armcloud.us/lava/common/linaro-image-minimal-initramfs-genericarmv7a.cpio.gz.u-boot
It has a u-boot header added, as most devices using this would be using u-boot and this makes it easier to debug boot failures as the initramfs doesn t need to have the header added, it can simply be downloaded to a local directory and passed to the board as a tftp location. To modify it, the u-boot header needs to be removed. Rather than assuming the size, the u-boot tools can (indirectly) show the size: 
$ ls -l linaro-image-minimal-initramfs-genericarmv7a.cpio.gz.u-boot
-rw-r--r-- 1 neil neil  5179571 Nov 26  2013 linaro-image-minimal-initramfs-genericarmv7a.cpio.gz.u-boot
$ mkimage -l linaro-image-minimal-initramfs-genericarmv7a.cpio.gz.u-boot 
Image Name:   linaro-image-minimal-initramfs-g
Created:      Tue Nov 26 22:30:49 2013
Image Type:   ARM Linux RAMDisk Image (gzip compressed)
Data Size:    5179507 Bytes = 5058.11 kB = 4.94 MB
Load Address: 00000000
Entry Point:  00000000
Referencing http://www.omappedia.com/wiki/Development_With_Ubuntu, the header size is the file size minus the data size listed by mkimage. 
5179571 - 5179507 == 64
So, create a second file without the header: 
dd if=linaro-image-minimal-initramfs-genericarmv7a.cpio.gz.u-boot of=linaro-image-minimal-initramfs-genericarmv7a.cpio.gz skip=64 bs=1
decompress it 
gunzip linaro-image-minimal-initramfs-genericarmv7a.cpio.gz
Now for the additions 
dget http://ftp.uk.debian.org/debian/pool/main/l/linux/linux-image-3.14-1-armmp_3.14.12-1_armhf.deb
(Yes, this process will need to be repeated when this package is rebuilt, so I ll want to script this at some point.) 
dpkg -x linux-image-3.14-1-armmp_3.14.12-1_armhf.deb kernel-dir
cd kernel-dir
Pulling in the modules we need for most needs, comes thanks to a script written by the Xen folks. The set is basically disk, net, filesystems and LVM. 
find lib -type d -o -type f -name modules.\*  -o -type f -name \*.ko  \( -path \*/kernel/lib/\* -o  -path \*/kernel/crypto/\* -o  -path \*/kernel/fs/mbcache.ko -o  -path \*/kernel/fs/ext\* -o  -path \*/kernel/fs/jbd\* -o  -path \*/kernel/drivers/net/\* -o  -path \*/kernel/drivers/ata/\* -o  -path \*/kernel/drivers/scsi/\* -o -path \*/kernel/drivers/md/\* \)   pax -x sv4cpio -s '%lib%/lib%' -d -w >../cpio
gzip -9f cpio
original Xen script (GPL-3+) I found it a bit confusing that i is used for extract by cpio, but that s how it is. Extract the minimal initramfs to a new directory: 
sudo cpio -id < ../linaro-image-minimal-initramfs-genericarmv7a.cpio
Extract the new cpio into the same location. (Yes, I could do this the other way around and pipe the output of find into the already extracted location but that's for when I get a script to do this): 
sudo cpio --no-absolute-filenames -id < ../ramfs/cpio
CPIO Manual Use newc format, the new (SVR4) portable format, which supports file systems having more than 65536 i-nodes. (4294967295 bytes)
(41M) 
find .   cpio -H newc -o > ../armmp-image.cpio
... and add the u-boot header back: 
mkimage -A arm -T ramdisk -C none -d armmp-image.cpio.gz debian-armmp-initrd.cpio.gz.u-boot
Now what? Now send the combination to LAVA and test it. Results bundle for a local LAVA test job using this technique. (18k) submission JSON - uses file:// references, so would need modification before being submitted to LAVA elsewhere. complete log of the test job (72k) Those familiar with LAVA will spot that I haven't optimised this job, it boots the ARMMP kernel into a minimal initramfs and then expects to find apt and other tools. Actual tests providing useful results would use available tools, add more tools or specify a richer rootfs. The tests themselves are very quick (the job described above took 3 minutes to run) and don't need to be run particularly often, just once per board type per upload of the ARMMP kernel. LAVA can easily run those jobs in parallel and submission can be automated using authentication tokens and the lava-tool CLI. lava-tool can be installed without lava-server, so can be used in hooks for automated submissions. Extensions That's just one DTB and one board. I have a range of boards available locally: * iMX6Q Wandboard (used for this test)
* iMX.53 Quick Start Board (needs updated u-boot)
* Beaglebone Black
* Cubie2
* CubieTruck
* arndale (no dtb?)
* pandaboard Other devices available could involve ARMv7 devices hosted at www.armv7.com and validation.linaro.org - as part of a thank you to the Debian community for providing the OS which is (now) running all of the LAVA infrastructure. That doesn't cover all of the current DTBs (and includes many devices which have no DTBs) so there is plenty of scope for others to get involved. Hopefully, the above will help get people started with a suitable kernel+dtb+initrd and I'd encourage anyone interested to install lava-server and have a go at running test jobs based on those so that we start to build data about as many of the variants as possible. (If anyone in DI fancies producing a suitable initrd with modules alongside the DI initrd for armhf builds, or if anyone comes up with a patch for DI to do that, it would help enormously.) This will at least help Debian answer the question of what the Debian ARMMP package can actually support. For help on LAVA, do read through the documentation and then come to us at #linaro-lava or the linaro-validation mailing list or file bugs in Debian: reportbug lava-server. , so you can ask me. I'm giving one talk on the LAVA software and there will be a BoF on validation and CI in Debian.

Russell Coker: Public Lectures About FOSS

Eventbrite I ve recently started using the Eventbrite Web site [1] and the associated Eventbrite Android app [2] to discover public events in my area. Both the web site and the Android app lack features for searching (I d like to save alerts for my accounts and have my phone notify me when new events are added to their database) but it is basically functional. The main issue is content, Eventbrite has a lot of good events in their database (I ve got tickets for 6 free events in the next month). I assume that Eventbrite also has many people attending their events, otherwise the events wouldn t be promoted there. At this time I haven t compared Eventbrite to any similar services, Eventbrite events have taken up much of my available time for the next 6 weeks (I appreciate the button on the app to add an entry to my calendar) so I don t have much incentive to find other web sites that list events. I would appreciate comments from users of competing event registration systems and may write a post in future comparing different systems. Also I have only checked for events in Melbourne, Australia as I don t have any personal interest in events in other places. For the topic of this post Eventbrite is good enough, it meets all requirements for Melbourne and I m sure that if it isn t useful in other cities then there are competing services. I think that we need to have free FOSS events announced through Eventbrite. We regularly have experts in various fields related to FOSS visiting Melbourne who give a talk for the Linux Users of Victoria (and sometimes other technical groups). This is a good thing but I think we could do better. Most people in Melbourne probably won t attend a LUG meeting and if they did they probably wouldn t find it a welcoming experience. Also I recommend that anyone who is looking for educational things to do in Melbourne visit the Eventbrite web site and/or install the Android app. Accessible Events I recently attended an Eventbrite event where a professor described the work of his research team, it was a really good talk that made the topic of his research accessible to random members of the public like me. Then when it came to question time the questions were mostly opinion pieces disguised as questions which used a lot of industry specific jargon and probably lost the interest of most people in the audience who wasn t from the university department that hosted the lecture. I spent the last 15 minutes in that lecture hall reading Wikipedia and resisted the temptation to load an Android game. Based on this lecture (and many other lectures I ve seen) I get the impression that when the speaker or the MC addresses a member of the audience by name (EG John Smith has a question ) then it s strongly correlated with a low quality question. See my previous post about the Length of Conference Questions for more on this topic [3]. It seems to me that when running a lecture everyone involved has to agree about whether it s a public lecture (IE one that is for any random people) as opposed to a society meeting (which while free for anyone to attend in the case of a LUG is for people with specific background knowledge). For a society meeting (for want of a better term) it s OK to assume a minimum level of knowledge that rules out some people. If 5% of the audience of a LUG don t understand a lecture that doesn t necessarily mean it s a bad lecture, sometimes it s not possible to give a lecture that is easily understood by those with the least knowledge that also teaches the most experienced members of the audience. For a public lecture the speaker has to give a talk for people with little background knowledge. Then the speaker and/or the MC have to discourage or reject questions that are for a higher level of knowledge. As an example of how this might work consider the case of an introductory lecture about how an OS kernel works. When one of the experienced Linux kernel programmers visits Melbourne we could have an Eventbrite event organised for a lecture introducing the basic concepts of an OS kernel (with Linux as an example). At such a lecture any questions about more technical topics (such as specific issues related to compilers, drivers, etc) could be met with we are having a meeting for more technical people at the Linux Users of Victoria meeting tomorrow night or we are having coffee at a nearby cafe afterwards and you can ask technical questions there . Planning Eventbrite Events When experts in various areas of FOSS visit Melbourne they often offer a talk for LUV. For any such experts who read this post please note that most lectures at LUV meetings are by locals who can reschedule, so if you are only in town for a short time we can give you an opportunity to speak at short notice. I would like to arrange to have some of those people give a talk aimed at a less experienced audience which we can promote through Eventbrite. The venue for LUV talks (Melbourne University 7PM on the first Tuesday of the month) might not work for all speakers so we need to find a sponsor for another venue. I will contact Linux companies that are active in Melbourne and ask whether they would be prepared to sponsor the venue for such a talk. The fallback option would be to have such a lecture at a LUV meeting. I will talk to some of the organisers of science and technology events advertised on Eventbrite and ask why they chose the times that they did. Maybe they have some insight into which times are best for getting an audience. Also I will probably get some idea of the best times by just attending many events and observing the attendance. I think that the aim of an Eventbrite event is to attract delegates who wouldn t attend other meetings, so it is a priority to choose a suitable time and place. Finally please note that while I am a member of the LUV committee I m not representing LUV in this post. My aim is that community feedback on this post will help me plan such events. I will discuss this with the LUV committee after I get some comments here. Please comment if you would like to give such a public lecture, attend such a lecture, or if you just have any general ideas.
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Andrew Pollock: [debian] Day 174: Kindergarten, startup stuff, tennis

I picked up Zoe from Sarah this morning and dropped her at Kindergarten. Traffic seemed particularly bad this morning, or I'm just out of practice. I spent the day powering through the last two parts of the registration block of my real estate licence training. I've got one more piece of assessment to do, and then it should be done. The rest is all dead-tree written stuff that I have to mail off to get marked. Zoe's doing tennis this term as her extra-curricular activity, and it's on a Tuesday afternoon after Kindergarten at the tennis court next door. I'm not sure what proportion of the class is continuing on from previous terms, and so how far behind the eight ball Zoe will be, but she seemed to do okay today, and she seemed to enjoy it. Megan's in the class too, and that didn't seem to result in too much cross-distraction. After that, we came home and just pottered around for a bit and then Zoe watched some TV until Sarah came to pick her up.

Hideki Yamane: GeoIP support for installer is really nice


RHEL7 installation note says "The new graphical installer also generates automatic default settings where applicable. For example, if the installer detects a network connection, the user's general location is determined with GeoIP and sane suggestions are made for the default keyboard layout, language and timezone." but CentOS7 doesn't work as expected ;-)

GeoIP support in Fedora20 Installer works well and it's pretty nice. Boot from live media and it shows "Try Fedora" and "Install to Hard Drive" menu.

Then, select "Install" and...Boom! it shows in Japanese without any configuration automagically!

I want same feature for d-i, too.

21 July 2014

Ian Campbell: sunxi-tools now available in Debian

I've recently packaged the sunxi tools for Debian. These are a set of tools produce by the Linux Sunxi project for working with the Allwinner "sunxi" family of processors. See the package page for details. Thanks to Steve McIntyre for sponsoring the initial upload. The most interesting component of the package are the tools for working with the Allwinner processors' FEL mode. This is a low-level processor mode which implements a simple USB protocol allowing for initial programming of the device and recovery which can be entered on boot (usually be pressing a special 'FEL button' somewhere on the device). It is thanks to FEL mode that most sunxi based devices are pretty much unbrickable. The most common use of FEL is to boot over USB. In the Debian package the fel and usb-boot tools are named sunxi-fel and sunxi-usb-boot respectively but otherwise can be used in the normal way described on the sunxi wiki pages. One enhancement I made to the Debian version of usb-boot is to integrate with the u-boot packages to allow you to easily FEL boot any sunxi platform supported by the Debian packaged version of u-boot (currently only Cubietruck, more to come I hope). To make this work we take advantage of Multiarch to install the armhf version of u-boot (unless your host is already armhf of course, in which case just install the u-boot package): 
# dpkg --add-architecture armhf
# apt-get update
# apt-get install u-boot:armhf
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following NEW packages will be installed:
  u-boot:armhf
0 upgraded, 1 newly installed, 0 to remove and 1960 not upgraded.
Need to get 0 B/546 kB of archives.
After this operation, 8,676 kB of additional disk space will be used.
Retrieving bug reports... Done
Parsing Found/Fixed information... Done
Selecting previously unselected package u-boot:armhf.
(Reading database ... 309234 files and directories currently installed.)
Preparing to unpack .../u-boot_2014.04+dfsg1-1_armhf.deb ...
Unpacking u-boot:armhf (2014.04+dfsg1-1) ...
Setting up u-boot:armhf (2014.04+dfsg1-1) ...
With that done FEL booting a cubietruck is as simple as starting the board in FEL mode (by holding down the FEL button when powering on) and then: 
# sunxi-usb-boot Cubietruck -
fel write 0x2000 /usr/lib/u-boot/Cubietruck_FEL/u-boot-spl.bin
fel exe 0x2000
fel write 0x4a000000 /usr/lib/u-boot/Cubietruck_FEL/u-boot.bin
fel write 0x41000000 /usr/share/sunxi-tools//ramboot.scr
fel exe 0x4a000000
Which should result in something like this on the Cubietruck's serial console: 
U-Boot SPL 2014.04 (Jun 16 2014 - 05:31:24)
DRAM: 2048 MiB
U-Boot 2014.04 (Jun 16 2014 - 05:30:47) Allwinner Technology
CPU:   Allwinner A20 (SUN7I)
DRAM:  2 GiB
MMC:   SUNXI SD/MMC: 0
In:    serial
Out:   serial
Err:   serial
SCSI:  SUNXI SCSI INIT
Target spinup took 0 ms.
AHCI 0001.0100 32 slots 1 ports 3 Gbps 0x1 impl SATA mode
flags: ncq stag pm led clo only pmp pio slum part ccc apst 
Net:   dwmac.1c50000
Hit any key to stop autoboot:  0 
sun7i#
As more platforms become supported by the u-boot packages you should be able to find them in /usr/lib/u-boot/*_FEL. There is one minor inconvenience which is the need to run sunxi-usb-boot as root in order to access the FEL USB device. This is easily resolved by creating /etc/udev/rules.d/sunxi-fel.rules containing either: 
SUBSYSTEMS=="usb", ATTR idVendor =="1f3a", ATTR idProduct =="efe8", OWNER="myuser"
or 
SUBSYSTEMS=="usb", ATTR idVendor =="1f3a", ATTR idProduct =="efe8", GROUP="mygroup"
To enable access for myuser or mygroup respectively. Once you have created the rules file then to enable: 
# udevadm control --reload-rules
As well as the FEL mode tools the packages also contain a FEX (de)compiler. FEX is Allwinner's own hardware description language and is used with their Android SDK kernels and the fork of that kernel maintained by the linux-sunxi project. Debian's kernels follow mainline and therefore use Device Tree.

Daniel Pocock: Australia can't criticize Putin while competing with him

While much of the world is watching the tragedy of MH17 and contemplating the grim fate of 298 deceased passengers sealed into a refrigerated freight train in the middle of a war zone, Australia (with 28 victims on that train) has more than just theoretical skeletons in the closet too. At this moment, some 153 Tamil refugees, fleeing the same type of instability that brought a horrible death to the passengers of MH17, have been locked up in the hull of a customs ship on the high seas. Windowless cabins and a supply of food not fit for a dog are part of the Government's strategy to brutalize these people for simply trying to avoid the risk of enhanced imprisonment(TM) in their own country. Under international protocol for rescue at sea and political asylum, these people should be taken to the nearest port and given a humanitarian visa on arrival. Australia, however, is trying to lie and cheat their way out of these international obligations while squealing like a stuck pig about the plight of Australians in the hands of Putin. If Prime Minister Tony Abbott wants to encourage Putin to co-operate with the international community, shouldn't he try to lead by example? How can Australians be safe abroad if our country systematically abuses foreigners in their time of need?

Steve Kemp: An alternative to devilspie/devilspie2

Recently I was updating my dotfiles, because I wanted to ensure that media-players were "always on top", when launched, as this suits the way I work. For many years I've used devilspie to script the placement of new windows, and once I googled a recipe I managed to achieve my aim. However during the course of my googling I discovered that devilspie is unmaintained, and has been replaced by something using Lua - something I like. I'm surprised I hadn't realized that the project was dead, although I've always hated the configuration syntax it is something that I've used on a constant basis since I found it. Unfortunately the replacement, despite using Lua, and despite being functional just didn't seem to gell with me. So I figured "How hard could it be?". In the past I've written softare which iterated over all (visible) windows, and obviously I'm no stranger to writing Lua bindings. However I did run into a snag. My initial implementation did two things: This worked. This worked well. This worked too well. The problem I ran into was that if I wrote something like "Move window 'emacs' to desktop 2" that action would be applied, over and over again. So if I launched emacs, and then manually moved the window to desktop3 it would jump back! In short I needed to add a "stop()" function, which would cause further actions against a given window to cease. (By keeping a linked list of windows-to-ignore, and avoiding processing them.) The code did work, but it felt wrong to have an ever-growing linked-list of processed windows. So I figured I'd look at the alternative - the original devilspie used libwnck to operate. That library allows you to nominate a callback to be executed every time a new window is created. If you apply your magic only on a window-create event - well you don't need to bother caching prior-windows. So in conclusion : I think my code is better than devilspie2 because it is smaller, simpler, and does things more neatly - for example instead of a function to get geometry and another to set it, I use one. (e.g. "xy()" returns the position of a window, but xy(3,3) sets it.). kpie also allows you to run as a one-off job, and using the simple primitives I wrote a file to dump your windows, and their size/placement, which looks like this: 
shelob ~/git/kpie $ ./kpie --single ./samples/dump.lua
-- Screen width : 1920
-- Screen height: 1080
..
if ( ( window_title() == "Buddy List" ) and
     ( window_class() == "Pidgin" ) and
     ( window_application() == "Pidgin" ) ) then
     xy(1536,24 )
     size(384,1032 )
     workspace(2)
end
if ( ( window_title() == "feeds" ) and
     ( window_class() == "Pidgin" ) and
     ( window_application() == "Pidgin" ) ) then
     xy(1,24 )
     size(1536,1032 )
     workspace(2)
end
..
As you can see that has dumped all my windows, along with their current state. This allows a simple starting-point - Configure your windows the way you want them, then dump them to a script file. Re-run that script file and your windows will be set back the way they were! (Obviously there might be tweaks required.) I used that starting-point to define a simple recipe for configuring pidgin, which is more flexible than what I ever had with pidgin, and suits my tastes. Bug-reports welcome.

Francois Marier: Creating a modern tiling desktop environment using i3

Modern desktop environments like GNOME and KDE involving a lot of mousing around and I much prefer using the keyboard where I can. This is why I switched to the Ion tiling window manager back when I interned at Net Integration Technologies and kept using it until I noticed it had been removed from Debian. After experimenting with awesome for 2 years and briefly considering xmonad , I finally found a replacement I like in i3. Here is how I customized it and made it play nice with the GNOME and KDE applications I use every day.

Startup script As soon as I log into my desktop, my startup script starts a few programs, including: Because of a bug in gnome-settings-daemon which makes the mouse cursor disappear as soon as gnome-settings-daemon is started, I had to run the following to disable the offending gnome-settings-daemon plugin: 
dconf write /org/gnome/settings-daemon/plugins/cursor/active false

Screensaver In addition, gnome-screensaver didn't automatically lock my screen, so I installed xautolock and added it to my startup script: 
xautolock -time 30 -locker "gnome-screensaver-command --lock" &
to lock the screen using gnome-screensaver after 30 minutes of inactivity. I can also trigger it manually using the following shortcut defined in my ~/.i3/config: 
bindsym Ctrl+Mod1+l exec xautolock -locknow

Keyboard shortcuts While keyboard shortcuts can be configured in GNOME, they don't work within i3, so I added a few more bindings to my ~/.i3/config: 
# volume control
bindsym XF86AudioLowerVolume exec /usr/bin/pactl set-sink-volume @DEFAULT_SINK@ -- '-5%'
bindsym XF86AudioRaiseVolume exec /usr/bin/pactl set-sink-volume @DEFAULT_SINK@ -- '+5%'
# brightness control
bindsym XF86MonBrightnessDown exec xbacklight -steps 1 -time 0 -dec 5
bindsym XF86MonBrightnessUp exec xbacklight -steps 1 -time 0 -inc 5
bindsym XF86AudioMute exec /usr/bin/pactl set-sink-mute @DEFAULT_SINK@ toggle
# show battery stats
bindsym XF86Battery exec gnome-power-statistics
to make volume control, screen brightness and battery status buttons work as expected on my laptop. These bindings require the following packages:

Keyboard layout switcher Another thing that used to work with GNOME and had to re-create in i3 is the ability to quickly toggle between two keyboard layouts using the keyboard. To make it work, I wrote a simple shell script and assigned a keyboard shortcut to it in ~/.i3/config: 
bindsym $mod+u exec /home/francois/bin/toggle-xkbmap

Suspend script Since I run lots of things in the background, I have set my laptop to avoid suspending when the lid is closed by putting the following in /etc/systemd/login.conf: 
HandleLidSwitch=lock
Instead, when I want to suspend to ram, I use the following keyboard shortcut: 
bindsym Ctrl+Mod1+s exec /home/francois/bin/s2ram
which executes a custom suspend script to clear the clipboards (using xsel), flush writes to disk and lock the screen before going to sleep. To avoid having to type my sudo password every time pm-suspend is invoked, I added the following line to /etc/sudoers: 
francois  ALL=(ALL)  NOPASSWD:  /usr/sbin/pm-suspend

Window and workspace placement hacks While tiling window managers promise to manage windows for you so that you can focus on more important things, you will most likely want to customize window placement to fit your needs better.

Working around misbehaving applications A few applications make too many assumptions about window placement and are just plain broken in tiling mode. Here's how to automatically switch them to floating mode: 
for_window [class="VidyoDesktop"] floating enable
You can get the Xorg class of the offending application by running this command: 
xprop   grep WM_CLASS
before clicking on the window.

Keeping IM windows on the first workspace I run Pidgin on my first workspace and I have the following rule to keep any new window that pops up (e.g. in response to a new incoming message) on the same workspace: 
assign [class="Pidgin"] 1

Automatically moving workspaces when docking Here's a neat configuration blurb which automatically moves my workspaces (and their contents) from the laptop screen (eDP1) to the external monitor (DP2) when I dock my laptop: 
# bind workspaces to the right monitors
workspace 1 output DP2
workspace 2 output DP2
workspace 3 output DP2
workspace 4 output DP2
workspace 5 output DP2
workspace 6 output eDP1
You can get these output names by running: 
xrandr --display :0   grep " connected"
Finally, because X sometimes fail to detect my external monitor when docking/undocking, I also wrote a script to set the displays properly and bound it to the appropriate key on my laptop: 
bindsym XF86Display exec /home/francois/bin/external-monitor

Keith Packard: Glamorous Intel

Reworking Intel Glamor The original Intel driver Glamor support was based on the notion that it would be better to have the Intel driver capture any fall backs and try to make them faster than Glamor could do internally. Now that Glamor has reasonably complete acceleration, and its fall backs aren t terrible, this isn t as useful as it once was, and because this uses Glamor in a weird way, we re making the Glamor code harder to maintain. Fixing the Intel driver to not use Glamor in this way took a bit of effort; the UXA support is all tied into the overall operation of the driver. Separating out UXA functions The first task was to just identify which functions were UXA-specific by adding _uxa to their names. A couple dozen sed runs and now a bunch of the driver is looking better. Next, a pile of UXA-specific functions were actually inside the non-UXA parts of the code. Those got moved out, and a new intel_uxa.h file was created to hold all of the definitions. Finally, a few non UXA-specific functions were actually in the uxa files; those got moved over to the generic code. Removing the Glamor paths in UXA Each one of the UXA functions had a little piece of code at the top like: 
if (uxa_screen->info->flags & UXA_USE_GLAMOR)  
    int ok = 0;
    if (uxa_prepare_access(pDrawable, UXA_GLAMOR_ACCESS_RW))  
        ok = glamor_fill_spans_nf(pDrawable,
                      pGC, n, ppt, pwidth, fSorted);
        uxa_finish_access(pDrawable, UXA_GLAMOR_ACCESS_RW);
     
    if (!ok)
        goto fallback;
    return;
Pulling those out shrank the UXA code by quite a bit. Selecting Acceleration (or not) The intel driver only supported UXA before; Glamor was really just a slightly different mode for UXA. I switched the driver from using a bit in the UXA flags to having an accel variable which could be one of three options: I added ACCEL_NONE to give us a dumb frame buffer mode. That actually supports DRI3 so that we can bring up Mesa and run it under X before we have any acceleration code ready; avoiding a dependency loop when doing new hardware. All that it requires is a kernel that offers mode setting and buffer allocation. Initializing Glamor With UXA no longer supporting Glamor, it was time to plug the Glamor support into the top of the driver. That meant changing a bunch of the entry points to select appropriate Glamor or UXA functionality, instead of just calling into UXA. So, now we ve got lots of places that look like: 
        switch (intel->accel)  
#if USE_GLAMOR
        case ACCEL_GLAMOR:
                if (!intel_glamor_create_screen_resources(screen))
                        return FALSE;
                break;
#endif
#if USE_UXA
        case ACCEL_UXA:
                if (!intel_uxa_create_screen_resources(screen))
                        return FALSE;
        break;
#endif
        case ACCEL_NONE:
                if (!intel_none_create_screen_resources(screen))
                        return FALSE;
                break;
Using a switch means that we can easily elide code that isn t wanted in a particular build. Of course accel is an enum, so places which are missing one of the required paths will cause a compiler warning. It s not all perfectly clean yet; there are piles of UXA-only paths still. Making It Build Without UXA The final trick was to make the driver build without UXA turned on; that took several iterations before I had the symbols sorted out appropriately. I built the driver with various acceleration options and then tried to count the lines of source code. What I did was just list the source files named in the driver binary itself. This skips all of the header files and the render program source code, and ignores the fact that there are a bunch of #ifdef s in the uxa directory selecting between uxa, glamor and none. 
    Accel                    Lines          Size(B)
    -----------             ------          -------
    none                      7143            73039
    glamor                    7397            76540
    uxa                      25979           283777
    sna                     118832          1303904
    none legacy              14449           152480
    glamor legacy            14703           156125
    uxa legacy               33285           350685
    sna legacy              126138          1395231
The legacy addition supports i810-class hardware, which is needed for a complete driver. Along The Way, Enable Tiling for the Front Buffer While hacking the code, I discovered that the initial frame buffer allocated for the screen was created without tiling (!) because a few parameters that depend on the GTT size were not initialized until after that frame buffer was allocated. I haven t analyzed what effect this has on performance. Page Flipping and Resize Page flipping (or just flipping) means switching the entire display from one frame buffer to another. It s generally the fastest way of updating the screen as you don t have to copy any bits. The trick with flipping is that a client hands you a random pixmap and you need to stuff that into the KMS API. With UXA, that s pretty easy as all pixmaps are managed through the UXA API which knows which underlying kernel BO is tied with each pixmap. Using Glamor, only the underlying GL driver knows the mapping. Fortunately (?), we have the EGL Image extension, which lets us take a random GL texture and turn it into a file descriptor for a DMA-BUF kernel object. So, we have this cute little dance: 
fd = glamor_fd_from_pixmap(screen,
                               pixmap,
                               &stride,
                               &size);
bo = drm_intel_bo_gem_create_from_prime(intel->bufmgr, fd, size);
    close(fd);
    intel_glamor_get_pixmap(pixmap)->bo = bo;
That last bit remembers the bo in some local memory so we don t have to do this more than once for each pixmap. glamorfdfrompixmap ends up calling eglCreateImageKHR followed by gbmbo_import and then a kernel ioctl to convert a prime handle into an fd. It s all quite round-about, but it does seem to work just fine. After I d gotten Glamor mostly working, I tried a few OpenGL applications and discovered flipping wasn t working. That turned out to have an unexpected consequence all full-screen applications would run flat-out, and not be limited to frame rate. Present recovers from a failed flip queue operation by immediately performing a CopyArea; not waiting for vblank. This needs to get fixed in Present by having it re-queued the CopyArea for the right time. What I did in the intel driver was to add a bunch more checks for tiling mode, pixmap stride and other things to catch pixmaps that were going to fail before the operation was queued and forcing them to fall back to CopyArea at the right time. The second adventure was with XRandR. Glamor has an API to fix up the screen pixmap for a new frame buffer, but that pulls the size of the frame buffer out of the pixmap instead of out of the screen. XRandR leaves the pixmap size set to the old screen size during this call; fixing that just meant getting the pixmap size set correctly before calling into glamor. I think glamor should get fixed to use the screen size rather than the pixmap size. Painting Root before Mode set The X server has generally done initialization in one order:
  1. Create root pixmap
  2. Set video modes
  3. Paint root window
Recently, we ve added a -background none option to the X server which causes it to set the root window background to none and have the driver fill in that pixmap with whatever contents were on the screen before the X server started. In a pre-Glamor world, that was done by hacking the video driver to copy the frame buffer console contents to the root pixmap as it was created. The trouble here is that the root pixmap is created long before the upper layers of the X server are ready for drawing, so you can t use the core rendering paths. Instead, UXA had kludges to call directly into the acceleration functions. What we really want though is to change the order of operations:
  1. Create root pixmap
  2. Paint root window
  3. Set video mode
That way, the normal root window painting operation will take care of getting the image ready before that pixmap is ever used for scanout. I can use regular core X rendering to get the original frame buffer contents into the root window, and even if we re not using -background none and are instead painting the root with some other pattern (like the root weave), I get that presented without an intervening black flash. That turned out to be really easy just delay the call to I830EnterVT (which sets the modes) until the server is actually running. That required one additional kludge I needed to tell the DIX level RandR functions about the new modes; the mode setting operation used during server init doesn t call up into RandR as RandR lists the current configuration after the screen has been initialized, which is when the modes used to be set. Calling xf86RandR12CreateScreenResources does the trick nicely. Getting the root window bits from fbcon, setting video modes and updating the RandR/Xinerama DIX info is now all done from the BlockHandler the first time it is called. Performance I ran the current glamor version of the intel driver with the master branch of the X server and there were not any huge differences since my last Glamor performance evaluation aside from GetImage. The reason is that UXA/Glamor never called Glamor s image functions, and the UXA GetImage is pretty slow. Using Mesa s image download turns out to have a huge performance benefit: 
1. UXA/Glamor from April
2. Glamor from today
       1                 2                 Operation
------------   -------------------------   -------------------------
     50700.0        56300.0 (     1.110)   ShmGetImage 10x10 square 
     12600.0        26200.0 (     2.079)   ShmGetImage 100x100 square 
      1840.0         4250.0 (     2.310)   ShmGetImage 500x500 square 
      3290.0          202.0 (     0.061)   ShmGetImage XY 10x10 square 
        36.5          170.0 (     4.658)   ShmGetImage XY 100x100 square 
         1.5           56.4 (    37.600)   ShmGetImage XY 500x500 square 
     49800.0        50200.0 (     1.008)   GetImage 10x10 square 
      5690.0        19300.0 (     3.392)   GetImage 100x100 square 
       609.0         1360.0 (     2.233)   GetImage 500x500 square 
      3100.0          206.0 (     0.066)   GetImage XY 10x10 square 
        36.4          183.0 (     5.027)   GetImage XY 100x100 square 
         1.5           55.4 (    36.933)   GetImage XY 500x500 square
Running UXA from today the situation is even more dire; I suspect that enabling tiling has made CPU reads through the GTT even worse than before? 
1: UXA today
2: Glamor today
       1                 2                 Operation
------------   -------------------------   -------------------------
     43200.0        56300.0 (     1.303)   ShmGetImage 10x10 square 
      2600.0        26200.0 (    10.077)   ShmGetImage 100x100 square 
       130.0         4250.0 (    32.692)   ShmGetImage 500x500 square 
      3260.0          202.0 (     0.062)   ShmGetImage XY 10x10 square 
        36.7          170.0 (     4.632)   ShmGetImage XY 100x100 square 
         1.5           56.4 (    37.600)   ShmGetImage XY 500x500 square 
     41700.0        50200.0 (     1.204)   GetImage 10x10 square 
      2520.0        19300.0 (     7.659)   GetImage 100x100 square 
       125.0         1360.0 (    10.880)   GetImage 500x500 square 
      3150.0          206.0 (     0.065)   GetImage XY 10x10 square 
        36.1          183.0 (     5.069)   GetImage XY 100x100 square 
         1.5           55.4 (    36.933)   GetImage XY 500x500 square
Of course, this is all just x11perf, which doesn t represent real applications at all well. However, there are applications which end up doing more GetImage than would seem reasonable, and it s nice to have this kind of speed up. Status I m running this on my crash box to get some performance numbers and continue testing it. I ll switch my desktop over when I feel a bit more comfortable with how it s working. But, I think it s feature complete at this point. Where s the Code As usual, the code is in my personal repository. It s on the glamor branch. 
git://people.freedesktop.org/~keithp/xf86-video-intel  glamor

20 July 2014

Laura Arjona: Upgrading my laptop to Debian Jessie

Some days ago I decided to upgrade my laptop from stable to testing. I had tried Jessie since several months, in my husband s laptop, but that was a fresh install, and a not-so-old laptop, and we have not much software installed there. In my netbook (Compaq Mini 110c), with stable, I already had installed Pumpa, Dianara and how-can-i-help from testing, and since the freeze is coming, I thought that I could full-upgrade and use Jessie from now on, and report my issues and help to diagnose or fix them, if possible, before the freeze. I keep Debian stable at work for my desktop and servers (well, some of them are still in oldstable, thanks LTS team!!), and I have testing in a laptop that I use as clonezilla/drbl server (but I had issues, next week I ll put some time on them and I ll write here my findings, and report bugs, if any). So! let s go. Here I write my experience and the issues that I found (very few! and not sure if they are bugs or configuration problems or what, I ll keep an eye on them). The upgrade I pointed my /etc/apt/sources.list to jessie, then apt-get update, then apt-get dist-upgrade. (With the servers I am much more careful, read the release notes, upgrade guides and so, or directly I go for a fresh install, but with my laptop, I am too lazy). I went to bed (wow, risky LArjona!) and when I got up for going to work, the laptop was waiting for me to accept to block root from ssh access, or restart some services, and so. Ok! the upgrade resumed but I have to go to work and I wanted my laptop! Since all the packages were already downloaded, I closed the lid (double risky LArjona!) unplugged it, put everything in my bag, and catched the bus in time :) At the bus, I opened again the lid of my laptop (crossing fingers!) and perfect, the laptop had suspended and returned back to life, and the upgrade just resumed with no problem. Wow! I love you Debian! After 15 minutes, I had to suspend again, since the bus arrived and I had to take the metro. In the metro, the upgrade resumed, and finished. I shutdown my laptop and arrive to work. Testing testing :) In a break for lunch, I opened my brand new laptop (the hardware is the same, but the software totally renewed, so it s brand new for me). I have to say that use xfce, with some GNOME/GTK apps installed (gedit, cheese, evince, XChat ) and some others that use Qt or are part of the KDE project (Okular, Kile, QtLinguist, Pumpa, Dianara). I don t know/care too much about desktops and tweaking my desktop: I just put the terminal and gedit in black background, Debian wallpaper is enough dark for me so ok, put the font size a bit smaller to better use my low-vertical-resolution, and that s all, I only go to configure something else if there s something that really annoys me. My laptop booted correctly and a nice, more modern LightDM was greeting me. I logged in and everything worked ok, except some issues that follow. Network Manager and WPA2-enterprise wireless connections I had to reconfigure some wireless connections in Network Manager. At the University we use WPA2-enterprise, TTLS + PAP. I had stored my username and password in the connection, and network manager seemed to remember the username but not the password. No problem, I said, and I wrote it when it asked, but the Save or OK button was greyed out. I could not click it. Then I went to edit the connections, and more or less the same, it seems that I could edit, but not save the (new) configuration. Finally, I removed the wireless connection and created it again, and everything worked as a charm. This, I had to do it with the two wireless in my University (both of them are WPA2-enterprise TTLS + PAP). At home, I have WPA2 personal, and I had no issues, everything worked ok. This problem is not appearing in a fresh install, since there are no old configs to keep. Adblock Plus not working any more I opened Iceweasel and I began to see ads in the webpages that I visited. What? I checked and Adblock plus was installed and activated I reinstalled the package xul-ext-adblock-plus and it worked again. Strange display in programs based on Qt When I opened Pumpa I noticed that the edges of the windows where too rough, as if it was not using a desktop theme. I asked to a friend that uses Plasma and he suggested to install qt4-qtconfig, and then, select a theme for my Qt apps. It worked like a charm, but I find strange that I didn t need it before in stable. Maybe the default xfce configuration from stable is setting a theme, and the new one is not setting it, and so, the Qt apps are left barefoot .
With qtconfig I chose a GTK+ Style GUI for my Qt apps and then, they looked similar to what I had in stable (frankly, I cannot say if it was similar or exactly the same , but I didn t find them strange as before, so I m fine). Strange display in programs from GNOME Well, this is not a Jessie problem, it s just that some programs adopted the new GNOME appearance, and since I m on xfce, not on GNOME, they look a bit strange (no menus integration, and so). I am not sure that I can run GNOME (fallback, classic?) in my 1 GB RAM laptop, I have to investigate if I can tweak it to use less memory, or what. I m not very tied to xfce, and in fact it does not look so light (well, on top of it, I don t run light programs, I run Iceweasel, Icedove, Libreoffice, and some others). At work I use GNOME in my desktop, but with GNOME shell, not the fallback or classic modes, so I m thinking about giving a chance to MATE or second chance to LXDE. We ll see. Issues when opening the lid (waking up from suspend) This is the most strange thing I found in the migration, and the most dangerous one, I think. As I said before, I don t tweak too much my desktop, if it works with the default configuration. I m not sure that I know the differences between suspend, hibernate, hard disks disconnections and so. When I was in stable, and I closed the lid of my laptop, it just shutdown the screen, then I heard something like the system going to suspend or whatever, and after some seconds, the harddisk and fans stop, the wireless led turns off, and the power led begins to blink. Ok. When I open the lid, then it was waking up itself (the power led stayed on, the wireless led turns on, and when I tap the touchpad or type anything, the screen was coming, with the xscreensaver asking for my password). Just sometimes, when the screen was turning on, I could see my desktop for less than a second, before xscreensaver turns the background black and asks for the password. Now since I migrated to Jessie, I m experiencing a different behavior. When I close the lid, the laptop behaves the same. When I open the lid, the laptop behaves the same, but when I type or tap the touchpad and xscreensaver comes to ask the password, before than I can type it, the laptop just suspends again (or hibernates, I m not sure), and I have to press the power button in order to bring it back to life (then I see the xscreensaver again asking for the password, I type it, and my desktop is there, the same as I left it when I closed the lid). Strange, isn t it? I have tried to suspend my laptop directly from the menu, and it comes to the same state in which I have to press the power button in order to bring it back to life, but then, no xscreensaver password is required (which is double strange, IMHO). Things I miss in Jessie Well, until now, the only thing I miss in Jessie is the software center. I rarely use it (I love apt) but I think it makes a good job in easing the installation of programs in Debian for people coming from other operative systems (specially after smartphones and their copied software stores became popular). I hope the maintainer can upload a new version before the freeze, and so, it enters in the release. I ll try to contact him. Update 2014/07/20: Julian Andres Klode, maintainer of software-center, just replied (see his comment below) and pointed to GNOME Software (gnome-packagekit) as alternative. I just installed and it looks neat and nice. I m very happy! TODO I have a Debian stable laptop at work (this one with xfce + GNOME), I ll try to upgrade it and see if I see the same problems that I notice in mine. Then, I ll check the corresponding packages to see if there are open bugs about them, and if not, report them to their maintainers. I have to review the wiki pages related to the Jessie Desktop theme selection, I think they wanted the wallpaper to be inside before the freeze. Maybe I can help in publicity about that, handle the votings and so. I like Joy, but it s time to change a bit, new fresh air into the room!
Filed under: My experiences and opinion Tagged: Contributing to libre software, Debian, English, Free Software, Moving into free software

John Goerzen: Beautiful Earth

Sometimes you see something that takes your breath away, maybe even makes your eyes moist. That happened when I saw this photo one morning: Sunrise on the Prairie Photography has been one of my hobbies since I was a child, and I ve enjoyed it all these years. Recently I was inspired by the growing ease of aerial photography using model aircraft, and now can fly two short-range RC quadcopters. That photo came from the first one, and despite being a low-res 1280 720 camera, tha image of our home in the yellow glow of sunrise brought a deep feeling a beauty and peace. DJI00196 Somehow seeing our home surrounded by the beauty of the immense wheat fields and green pastures drives home how small we all are in comparison to the vastness of the earth, and how lucky we are to inhabit this beautiful planet. DJI00204 As the sun starts to come up over the pasture, the only way you can tell the height of the grass at 300ft is to see the shadow it makes on the mowed pathway Laura and I use to get down to the creek. DJI00149 This is a view of our church in a small town nearby the church itself is right in the center of the photo. Off to the right, you see the grain elevators that can be seen for miles across the Kansas prairie, and of course the fields are never all that far off in the background. Here you can see the quadcopter taking off from the driveway: And here it is flying over my home church out in the country: DJI00120 That s the country church, at the corner of two gravel roads with its lighted cross facing east that can be seen from a mile away at night. To the right is the church park, and the green area along the road farther back is the church cemetery. DJI00063 Sometimes we get in debates about environmental regulations, politics, religion, whatever. We hear stories of missiles, guns, and destruction. It is sad, this damage we humans inflict on ourselves and our earth. Our earth our home is worth saving. Its stunning beauty from all its continents is evidence enough of that. To me, this photo of a small corner of flat Kansas is proof enough that the home we all share deserves to be treated well, and saved so that generations to come can also get damp eyes viewing its beauty from a new perspective. DJI00183

19 July 2014

Steve Kemp: Did you know xine will download and execute scripts?

Today I was poking around the source of Xine, the well-known media player. During the course of this poking I spotted that Xine has skin support - something I've been blissfully ignorant of for many years. How do these skins work? You bring up the skin-browser, by default this is achieved by pressing "Ctrl-d". The browser will show you previews of the skins available, and allow you to install them. How does Xine know what skins are available? It downloads the contents of: NOTE: This is an insecure URL. The downloaded file is a simple XML thing, containing references to both preview-images and download locations. For example the theme "Sunset" has the following details: if you choose to install the skin the Sunset.tar.gz file is downloaded, via HTTP, extracted, and the shell-script doinst.sh is executed, if present. So if you control DNS on your LAN you can execute arbitrary commands if you persuade a victim to download your "corporate xine theme". Probably a low-risk attack, but still a surprise.

Vasudev Kamath: Stop messing with my settings Network Manager

I use a laptop with Atheros wifi card with ath9k driver. I use hostapd to convert my laptop wifi into AP (Access point) so I can share network with my Nexus 7 and Kindle. This has been working fine for quite some time till my recent update. After recent system update (I use Debian Sid), I couldn't for some reason convert my wifi into AP so my device can connect. I can't find anything in log nor in hostapd debug messages which is useful to trouble shoot the issue. Every time I start the laptop my wifi card will be blocked by RF-KILL and I have manually unblock (both hard and soft). The script which I use to convert my Wifi into AP is below 
#Initial wifi interface configuration
ifconfig "$1" up 192.168.2.1 netmask 255.255.255.0
sleep 2
# start dhcp
sudo systemctl restart dnsmasq.service
iptables --flush
iptables --table nat --flush
iptables --delete-chain
iptables -t nat -A POSTROUTING -o "$2" -j MASQUERADE
iptables -A FORWARD -i "$1" -j ACCEPT
sysctl -w net.ipv4.ip_forward=1
#start hostapd
hostapd /etc/hostapd/hostapd.conf  &> /dev/null &
I tried rebooting the laptop and for some time I managed to convert my wifi into AP, I noticed at same time that Network Manager is not started once laptop is booted, yeah this also started happening after recent upgrade which I guess is the black magic of systemd. After some time I noticed wifi has went down and now I can't bring it up because its blocked by RF-KILL. After checking the syslog I noticed following lines. 
Jul 18 23:09:30 rudra kernel: [ 1754.891060] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Jul 18 23:09:30 rudra NetworkManager[5485]: <info> (mon.wlan0): using nl80211 for WiFi device control
Jul 18 23:09:30 rudra NetworkManager[5485]: <info> (mon.wlan0): driver supports Access Point (AP) mode
Jul 18 23:09:30 rudra NetworkManager[5485]: <info> (mon.wlan0): new 802.11 WiFi device (driver: 'ath9k' ifindex: 10)
Jul 18 23:09:30 rudra NetworkManager[5485]: <info> (mon.wlan0): exported as /org/freedesktop/NetworkManager/Devices/8
Jul 18 23:09:30 rudra NetworkManager[5485]: <info> (mon.wlan0): device state change: unmanaged -> unavailable (reason 'managed') [10 20 2]
Jul 18 23:09:30 rudra NetworkManager[5485]: <info> (mon.wlan0): preparing device
Jul 18 23:09:30 rudra NetworkManager[5485]: <info> devices added (path: /sys/devices/pci0000:00/0000:00:1c.1/0000:04:00.0/net/mon.wlan0, iface: mon.wlan0)
Jul 18 23:09:30 rudra NetworkManager[5485]: <info> device added (path: /sys/devices/pci0000:00/0000:00:1c.1/0000:04:00.0/net/mon.wlan0, iface: mon.wlan0): no ifupdown configuration found.
Jul 18 23:09:33 rudra ModemManager[891]: <warn>  Couldn't find support for device at '/sys/devices/pci0000:00/0000:00:1c.1/0000:04:00.0': not supported by any plugin
Well I couldn't figure out much but it looks like NetworkManager has come up and after seeing interface mon.wlan0, a monitoring interface created by hostapd to monitor the AP goes mad and tries to do something with it. I've no clue what it is doing and don't have enough patience to debug that. Probably some expert can give me hints on this. So as a last resort I purged the NetworkManager completely from the system and settled back to good old wicd and rebooted the system. After reboot wifi card is happy and is not blocked by RF-KILL and now I can convert it AP and use it as long as I wish without any problems. Wicd is not a great tool but its good enough to get the job done and does only what is asked to it unlike the NetworkManager. So in short
NetworkManager please stop f***ing with my settings and stop acting oversmart.

18 July 2014

Osamu Aoki: Debian does not boot ...Crucial/Micron RealSSD m4/C400/P400

Today, my PC did not boot as usual to Debian. BIOS could not find my /dev/sda and was looking for the netboot image. I restarted my PC and got into the BIOS boot setting menu. Hmmm.... my first SDD (/dev/sda) was missing. My second HDD (/dev/sdb) was there. But I did not put the Grub boot-loader there. No wonder it did not boot.

I have a 32GB USB3 stick with the full Debian system. It is not a live CD image USB stick but a HDD formatted and encrypted system. Though it is not the fastest system, it is very light and usable. I plugged it in and powered it up. It booted OK but /dev/sda was still missing. While it booted, I saw "ata1: COMRESET failed (errorno=-16)" . So this ata1 SSD cannot be accessed from BIOS nor Linux. Sigh ...

Looking around the web under the USB stick system, I saw some people were talking that the loose serial ATA cable sometimes causes this message. Since my PC is a laptop, It has no flexible cable but has an on-board connector inside for the SSD.

Hoping my problem is just a bad connection problem, I crack opened the back panel of my PC. The SSD looked fine. I unplugged it from the connector and reinserted back into the connector. After repeating this several times to be sure, I closed the back panel and booted.

It boots as expected into Debian. Looks like everything is fine.
SMART Error Log Version: 1
No Errors Logged
Good.

If you have any boot problem like mine, please reinsert your SSD to the connector like I did before you panic.

Good luck.

Osamu

PS: This Crucial/Micron RealSSD m4/C400/P400 M4-CT256M4SSD2 previously had a problem. A firmware bug made it read-only. The firmware updates fixed my Debian system on this SSD. I could fix this without Win*** OS since the firmware update was on a bootable disk image file.

Mario Lang: Croudsourced accessibility: Self-made digital menus

Something straight out from the real world: Menu cards in restaurants are not nice to deal with if you are blind. It is an old problem we grow used to ignoring over time, but still something that can be quite nagging. There are a lot of psychological issues involved in this one. Of course, you can ask for the menu to be read out to you by the staff. While they usually do their best, you end up missing out on some things most of the time. First of all, depending on the current workload in the restaurant, the staff will usually try to cut some time and not read everything to you. What they usually do is to try to understand what type of meal you are interested in, and just read the choices from that category to you. While this can be considered a service in some situations (human preprocessing), there are situations were you will definitely miss a highlight on the menu that you would have liked to choose if you knew that it was there. And even if the staff decides to read the complete menu to you (which is rare), you are confronted with the 7-things-in-my-head-at-once problem. It is usually rather hard to decide amongst a list of more then 7 items, because our short-term memory is sort of limited. What the sighted restaurant goers do, is to skip back and forth between the available options, until they hit a decisive moment. True, that can take a while, but it is definitely a lot easier if you can perform "random access reads" to the list of choices yourself. However, if someone presents a substantial number of choices to you in a row, as sequential speech, you loose the random access ability. You either remember every choice from the beginning and do your choosing mentaully (if you do have extraordinary mental abilities), or you end up asking the staff to read previous items aloud again. This can work, but usually it doesn't. At some point, you do not want to bother the staff anymore, and you even start to feel stupid for asking again and again, while this is something totally normal to every sighted person, just that "they" do their "random access browsing" on their own, so "they" have no need to feel bad about how long it takes them to decide, minus the typical social pressure that arises after a a certain time for everyone, at least if you are dining in a group. In very rare cases, you happen to meet staff that is truly "awake", doing their best to not let you feel that they might be pressed on time, and really taking as much time as necessary to help you make the perfect decision. This is rare, but if it happens, it is almost a magical moment. One of these moments, where there are no "artificial" barriers between humans doing communcation. Anyway, I am drifting away. The perfect solution to this problem is to provide random access browsing of a restaurant menu with the help of digital devices. Trying to make braille menus available in all restaurants is a goal which is not realistically reachable. Menus go out of date, and need changing. And getting a physical braille copy updated and reprinted is considerably more involved as with digital media. Restaurant owners will also likely not see the benefit to rpvide a braille card for a very small circle of customers. With a digital online menu, that is a completely different story. These days, almost every blind person in at least my social circles owns an iOS (or similar) device. These devices have speech synthesis and web browsers. Of course, some restaurants especially in urban areas do already have a menu online. I have found them manually with google and friends sometimes in the past, which has already given me the ability to actually sit back, and really comfortably choose amongst the available offerings myself, without having to bother a human, and without having to feel bad about (ab)using their time. However, the case where a restaurant really has their menu online is rather rare still in the area where I am. And, it can be tedious to google for a restaurant website. Sometimes, the website itself is just marginally accessible, which makes it even more frustrating to get a relaxed dinner-experience. I have discovered a location-based solution for the restaurant-menu problem recently. Foursquare offers the ability to provide a direct link to the menu in a restaurant-entry. I figured, since all you need to do is write a single webpage where the (common) menu items are listed per restaurant, that I could begin to create restaurant menus for my favourite locations, on my own. Well, not quite, but almost. I will sometimes need help from others to get the menu digitized, but that's just a one-time piece of work I hopefully can outsource :-). Once the actual content is in my INBUX, I create a nice HTML page listing the menu in a rather speech-based browser friendly way. I have begun to do this today, with the menu of a restaurant just about 500 meters away from my apartment. Unterm goldenen Dachl now has a menu online, and the foursquare change request to publish the corresponsing URL is already pending. I don't fully understand how the Foursquare change review process works yet, but I hope the URL should be published in the upcoming days/weeks. I am using Foursquare because it is the backend of a rather popular mobile navigation App for blind people, called Blindsquare. Blindsquare lets you comfortably use Open Street Map and Foursquare data to get an overview of your surroundingds. If a food place has a menu entry listed in Foursquare, Blindsquare conveniently shows it to you and opens a browser if you tap it. So there is no need to actually search for the restaurant, you can just use the location based search of Blindsquare to discover the restaurant entry and its menu link directly from within Blindsquare. Actually, you could even find a restaurant by accident, and with a little luck, find the menu for it by location, without even knowing how the restaurant is called. Isn't that neat? Yeah, that's how it is supposed to work, that's as much independence as you can get. And, it is, as the title suggests, croudsourced accessibility. Becuase while it is nice if a restaurant owner cares to publish their menu themselves, if they haven't, you can do it yourself. Either as a user of assistive technologies, to scratch your own itch. Or as a friend of a person with a need for assistive technologies. Next time you go to lunch with your blind friend, consider making available the menu to them digitally in advance, instead of reading it. Other people will likely thank you for that, and you have actually achieved something today. And if you happne to put a menu online, make sure to submit a change request to Foursquare. Many blind people are using blindsquare these days, which makes it super-easy for them to discover the menu.

17 July 2014

Jonathan McDowell: On the state of Free VoIP

Every now and then I decide I'll try and sort out my VoIP setup. And then I give up. Today I tried again. I really didn't think I was aiming that high. I thought I'd start by making my email address work as a SIP address. Seems reasonable, right? I threw in the extra constraints of wanting some security (so TLS, not UDP) and a soft client that would work on my laptop (I have a Grandstream hardphone and would like an Android client as well, but I figure those are the easy cases while the "I have my laptop and I want to remain connected" case is a bit trickier). I had a suitable Internet connected VM, access to control my DNS fully (so I can do SRV records) and time to read whatever HOWTOs required. And oh my ghod the state of the art is appalling. Let's start with getting a SIP server up and running. I went with repro which seemed to be a reasonably well recommended SIP server to register against. And mostly getting it up and running and registering against it is fine. Until you try and make a TLS SIP call through it (to a sip5060.net test address). Problem the first; the StartCom free SSL certs are not suitable because they don't advertise TLS Client. So I switch to CACert. And then I get bitten by the whole question about whether the common name on the cert should be the server name, or the domain name on the SIP address (it's the domain name on the SIP address apparently, though that might make your SIP client complain). That gets the SIP side working. Of course RTP is harder. repro looks like it's doing the right thing. The audio never happens. I capitulate at this point, and install Lumicall on my phone. That registers correctly and I can call the sip:test.time@sip5060.net test number and hear the time. So the server is functioning, it's the client that's a problem. I try the following (Debian/testing): I'm bored at this point. Can I "dial" my debian.org SIP address from Lumicall? Of course not; I get a "Codecs incompatible" (SIP 488 Not Acceptable Here) response. I have no idea what that means. I seem to have all of the options on Lumicall enabled. Is it a NAT thing? A codec thing? Did I sacrifice the wrong colour of goat? At some point during this process I get a Skype call from some friends, which I answer. Up comes a video call with them, their newborn, perfect audio, and no hassle. I have a conversation with them that doesn't involve me cursing technology at all. And then I go back to fighting with SIP. Gunnar makes the comment about Skype creating a VoIP solution 10 years ago when none was to be found. I believe they're still the market leader. It just works. I'm running the Linux client, and they're maintaining it (a little behind the curve, but close enough), and it works for text chat, voice chat and video calls. I've spent half a day trying to get a Free equivalent working and failing. I need something that works behind NAT, because it's highly likely when I'm on the move that's going to be the case. I want something that lets my laptop be the client, because I don't want to rely on my mobile phone. I want my email address to also be my VoIP address. I want some security (hell, I'm not even insisting on SRTP, though I'd like to). And the state of the Open VoIP stack just continues to make me embarrassed. I haven't given up yet, but I'd appreciate some pointers. And Skype, if you're hiring, drop me a line. ;)

Daniel Pocock: MH17 and the elephant in the room

Just last week, air passengers were told of intrusive new checks on their electronic devices when flying. For years, passengers have also suffered bans on basic essentials like drinking water and excesses like the patting down of babies that even Jimmy Saville would find offensive. Of course, all this is being done for public safety. So if western leaders claim the safety and security of their citizens is really their number one priority, just how is it that a passenger aircraft can be flying through a war zone where two other planes were shot down this month? When it comes to aviation security, this really is the elephant in the room. The MH17 tragedy today demonstrates that terror always finds a way. It is almost like the terrorists can have their cake and eat it too: they force "free" countries to give up their freedoms and public decency and then they still knock the occasional plane out of the sky anyway. History in the making? It is 100 years since the assassination of Austrian Archduke Franz Ferdinand started World War I and just over 50 years since the Cuban missile crisis. Will this incident also achieve similar notoriety in history? The downing of MH17 may well have been a "mistake" but the casualties are real and very tragic indeed. I've flown with Malaysia Airlines many times, including the same route MH17 and feel a lot of sympathy for these people who have been affected.

Craig Small: No more dspam, now what?

I was surprised at first to see that a long-standing bug in dspam had been fixed. Until that is, I realised it was from the Debian ftp masters and the reason the bug was closing was that dspam was being removed from the Debian archive. Damn! So, now what? What is a good replacement for dspam that is actually maintained? I don t need anti-virus because mutt just ignores those sorts of things and besides youbankdetails.zip.exe doesn t run too well on Debian. dspam basically used tokens to find common patterns of spam and ham, with you bouncing misses so it learnt from its mistakes. Already got postgrey running for greylisting so its really something that does the bayesan filtering. Some intial comments: There really is only me on the mailserver with a pretty light load so no need to worry about efficiencies. Not sure if it matters but my MTA is postfix and I already use procmail for delivery.

16 July 2014

Matthias Klumpp: AppStream 0.7 specification and library released

appstream-logoToday I am very happy to announce the release of AppStream 0.7, the second-largest release (judging by commit number) after 0.6. AppStream 0.7 brings many new features for the specification, adds lots of good stuff to libappstream, introduces a new libappstream-qt library for Qt developers and, as always, fixes some bugs. Unfortunately we broke the API/ABI of libappstream, so please adjust your code accordingly. Apart from that, any other changes are backwards-compatible. So, here is an overview of what s new in AppStream 0.7: Specification changes Distributors may now specify a new <languages/> tag in their distribution XML, providing information about the languages a component supports and the completion-percentage for the language. This allows software-centers to apply smart filtering on applications to highlight the ones which are available in the users native language. A new addon component type was added to represent software which is designed to be used together with a specific other application (think of a Firefox addon or GNOME-Shell extension). Software-center applications can group the addons together with their main application to provide an easy way for users to install additional functionality for existing applications. The <provides/> tag gained a new dbus item-type to expose D-Bus interface names the component provides to the outside world. This means in future it will be possible to search for components providing a specific dbus service: 
$ appstream-index what-provides dbus org.freedesktop.PackageKit.desktop system
(if you are using the cli tool) A <developer_name/> tag was added to the generic component definition to define the name of the component developer in a human-readable form. Possible values are, for example The KDE Community , GNOME Developers or even the developer s full name. This value can be (optionally) translated and will be displayed in software-centers. An <update_contact/> tag was added to the specification, to provide a convenient way for distributors to reach upstream to talk about changes made to their metadata or issues with the latest software update. This tag was already used by some projects before, and has now been added to the official specification. Timestamps in <release/> tags must now be UNIX epochs, YYYYMMDD is no longer valid (fortunately, everyone is already using UNIX epochs). Last but not least, the <pkgname/> tag is now allowed multiple times per component. We still recommend to create metapackages according to the contents the upstream metadata describes and place the file there. However, in some cases defining one component to be in multiple packages is a short way to make metadata available correctly without excessive package-tuning (which can become difficult if a <provides/> tag needs to be satisfied). As small sidenote: The multiarch path in /usr/share/appdata is now deprecated, because we think that we can live without it (by shipping -data packages per library and using smarter AppStream metadata generators which take advantage of the ability to define multiple <pkgname/> tags) Documentation updates In general, the documentation of the specification has been reworked to be easier to understand and to include less duplication of information. We now use excessive crosslinking to show you the information you need in order to write metadata for your upstream project, or to implement a metadata generator for your distribution. Because the specification needs to define the allowed tags completely and contain as much information as possible, it is not very easy to digest for upstream authors who just want some metadata shipped quickly. In order to help them, we now have Quickstart pages in the documentation, which are rich of examples and contain the most important subset of information you need to write a good metadata file. These quickstart guides already exist for desktop-applications and addons, more will follow in future. We also have an explicit section dealing with the question How do I translate upstream metadata? now. More changes to the docs are planned for the next point releases. You can find the full project documentation at Freedesktop. AppStream GObject library and tools The libappstream library also received lots of changes. The most important one: We switched from using LGPL-3+ to LGPL-2.1+. People who know me know that I love the v3 license family of GPL licenses I like it for tivoization protection, it s explicit compatibility with some important other licenses and cosmetic details, like entities not loosing their right to use the software forever after a license violation. However, a LGPL-3+ library does not mix well with projects licensed under other open source licenses, mainly GPL-2-only projects. I want libappstream to be used by anyone without forcing the project to change its license. For some reason, using the library from proprietary code is easier than using it from a GPL-2-only open source project. The license change was also a popular request of people wanting to use the library, so I made the switch with 0.7. If you want to know more about the LGPL-3 issues, I recommend reading this blogpost by Nikos (GnuTLS). On the code-side, libappstream received a large pile of bugfixes and some internal restructuring. This makes the cache builder about 5% faster (depending on your system and the amount of metadata which needs to be processed) and prepares for future changes (e.g. I plan to obsolete PackageKit s desktop-file-database in the long term). The library also brings back support for legacy AppData files, which it can now read. However, appstream-validate will not validate these files (and kindly ask you to migrate to the new format). The appstream-index tool received some changes, making it s command-line interface a bit more modern. It is also possible now to place the Xapian cache at arbitrary locations, which is a nice feature for developers. Additionally, the testsuite got improved and should now work on systems which do not have metadata installed. Of course, libappstream also implements all features of the new 0.7 specification. With the 0.7 release, some symbols were removed which have been deprecated for a few releases, most notably as_component_get/set_idname, as_database_find_components_by_str, as_component_get/set_homepage and the pkgname property of AsComponent (which is now a string array and called pkgnames ). API level was bumped to 1. Appstream-Qt A Qt library to access AppStream data has been added. So if you want to use AppStream metadata in your Qt application, you can easily do that now without touching any GLib/GObject based code! Special thanks to Sune Vuorela for his nice rework of the Qt library! And that s it with the changes for now! Thanks to everyone who helped making 0.7 ready, being it feedback, contributions to the documentation, translation or coding. You can get the release tarballs at Freedesktop. Have fun!

Dirk Eddelbuettel: Introducing RcppParallel: Getting R and C++ to work (some more) in parallel

A common theme over the last few decades was that we could afford to simply sit back and let computer (hardware) engineers take care of increases in computing speed thanks to Moore's law. That same line of thought now frequently points out that we are getting closer and closer to the physical limits of what Moore's law can do for us. So the new best hope is (and has been) parallel processing. Even our smartphones have multiple cores, and most if not all retail PCs now possess two, four or more cores. Real computers, aka somewhat decent servers, can be had with 24, 32 or more cores as well, and all that is before we even consider GPU coprocessors or other upcoming changes. And sometimes our tasks are embarassingly simple as is the case with many data-parallel jobs: we can use higher-level operations such as those offered by the base R package parallel to spawn multiple processing tasks and gather the results. I covered all this in some detail in previous talks on High Performance Computing with R (and you can also consult the Task View on High Performance Computing with R which I edit). But sometimes we can't use data-parallel approaches. Hence we have to redo our algorithms. Which is really hard. R itself has been relying on the (fairly mature) OpenMP standard for some of its operations. Luke Tierney's (awesome) keynote in May at our (sixth) R/Finance conference mentioned some of the issues related to OpenMP. One which matters is that OpenMP works really well on Linux, and either not so well (Windows) or not at all (OS X, due the usual issue with the gcc/clang switch enforced by Applem but the good news is that the OpenMP toolchain is expected to make it to OS X is some more performant form "soon"). R is still expected to make wider use of OpenMP in future versions. Another tool which has been around for a few years, and which can be considered to be equally mature is the Intel Threaded Building Blocks library, or TBB. JJ recently started to wrap this up for use by R. The first approach resulted in a (now superseded, see below) package TBB. But hardware and OS issues bite once again, as the Intel TBB is not really building that well for the Windows toolchain used by R (and based on MinGW). (And yes, there are two more options. But Boost Threads requires linking which precludes easy use as e.g. via our BH package. And C++11 with its threads library (based on Boost Threads) is not yet as widely available as R and Rcpp which means that it is not a real deployment option yet.) Now, JJ, being as awesome as he is, went back to the drawing board and integrated a second threading toolkit: TinyThread++, a small header-only library without further dependencies. Not as feature-rich as Intel Threaded Building Blocks, but at least available everywhere. So a new package RcppParallel, so far only on GitHub, wraps around both TinyThread++ and Intel Threaded Building Blocks and offers a consistent interface available on all platforms used by R. Better still, JJ also authored several pieces demonstrating this new package for the Rcpp Gallery: All four are interesting and demonstrate different aspects of parallel computing via RcppParallel. But the last article is key. Based on a question by Jim Bullard, and then written with Jim, it shows how a particular matrix distance metric (which is missing from R) can be implemented in a serial manner in both R, and also via Rcpp. The key implementation, however, uses both Rcpp and RcppParallel and thereby achieves a truly impressive speed gain as the gains from using compiled code (via Rcpp) and from using a parallel algorithm (via RcppParallel) are multiplicative! Between JJ's and my four-core machines the gain was between 200 and 300 fold---which is rather considerable. For kicks, I also used a much bigger machine at work which came in at an even larger speed gain (but gains become clearly sublinear as the number of cores increases; there are however some tuning parameters). So these are exciting times. I am sure there will be lots more to come. For now, head over to the RcppParallel package and start playing. Further contributions to the Rcpp Gallery are not only welcome but strongly encouraged.

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