Enrico's blog
Last 10 blog posts
5 years of Debian Diversity Statement
The Debian Project welcomes and encourages participation by everyone.
No matter how you identify yourself or how others perceive you: we welcome you. We welcome contributions from everyone as long as they interact constructively with our community.
While much of the work for our project is technical in nature, we value and encourage contributions from those with expertise in other areas, and welcome them into our community.
The Debian Diversity Statement has recently turned 5 years old, and I still find it the best diversity statement I know of, one of the most welcoming texts I've seen, and the result of one of the best project-wide mailing list discussions I can remember.
debian eng pdoToday I Learnt
Build a system that can install GRUB2 on UEFI and on legacy systems
grub-efi-amd64 and grub-pc are not coinstallable. It turns out however that
they do not contain GRUB, but the machinery to keep GRUB configuration up to
date on the current system. If I want to be able to install GRUB on other
systems, I can use the -bin packages:
apt install grub-common grub2-common grub-efi-amd64-bin grub-pc-bin
That gave me a grub-install command that worked on both kinds of systems.
GRUB configuration on a UEFI system
An old GRUB configuration on a UEFI system gave me this:
error: no suitable mode found Booting blind
which boots on a blank screen until the kernel reinitialises the video hardware.
The Arch Linux Wiki has excellent documentation for this case, and here's the resulting UEFI GRUB snippet:
insmod efi_gop insmod efi_uga insmod font if loadfont ${prefix}/fonts/unicode.pf2 then insmod gfxterm set gfxmode=auto set gfxpayload=keep terminal_output gfxterm fi # Follow with the usual GRUB menu entries…
Use an unsigned local APT repository for testing/development purposes
I found out today that one can have options in square brackets in sources.list:
# In /etc/apt/sources.list.d/local-devel.list deb [trusted=yes] http://localhost:1234/debian jessie main
pabs on IRC also mentioned local-apt-repository but I haven't tried it.
Booting Jessie Debian Live with a kernel from jessie-backports
This requires working around #844749 and 844749.
In hooks/9000-fix-bugs.chroot I ended up having this:
# Workaround per https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=844749 if ! grep -q ^nls_ascii /etc/initramfs-tools/modules then echo "nls_ascii" >> /etc/initramfs-tools/modules fi # Workaround per https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=844749 if ! grep -q ^overlay /etc/initramfs-tools/modules then echo "overlay" >> /etc/initramfs-tools/modules fi
Using a custom kernel in Jessie Debian Live
How do I have live-build pick a custom kernel package instead of the default one?
lb config --linux-packages linux-image-$SOMETHING- Use equivs to build a
linux-image-$SOMETHING-$ARCHpackage that depends on the kernel that you built.
Debian Jessie Live on UEFI part 2
A refinement on my previous attempt.
This is how to configure a Jessie live-build environment to boot on UEFI systems, and get a USB key image that works:
# Build a FAT image instead of an ISO image... lb config -b hdd # ...and work around #773833 echo "/usr/lib/syslinux/mbr/*.bin /usr/lib/syslinux/" > hooks/9000-fix-773833.chroot # Get EFI Shell from https://svn.code.sf.net/p/edk2/code/trunk/edk2/ShellBinPkg/UefiShell/X64/ curl -o binary/efi/boot/Bootx64.efi https://svn.code.sf.net/p/edk2/code/trunk/edk2/ShellBinPkg/UefiShell/X64/Shell.efi # Configure the EFI shell to boot the live setup echo 'live\vmlinuz initrd=live\initrd.img append boot=live components' > binary/startup.nsh
Rationale: UEFI understants FAT filesystems, and would run EFI binaries placed under efi/boot.
For a hard drive, it only considers a FAT filesystem on a GPT partition marked with a special UUID, so that it doesn't get confused with other FAT filesystems that are on disk.
For a USB key, it seems that most hardware will happily look for efi/boot
even if the partition table is the old MBR kind.
live-build can build a FAT image for USB keys, losing the ability to boot on
CDROMs and DVDs. Since I don't need that ability, I can use -b hdd to get the
live system packaged inside a container that UEFI hardware can understand
(FAT).
At that point, enabling UEFI boot on a Live Debian Jessie is just a matter of
adding an efi/boot/Bootx64.efi binary that is able to load the kernel and
initrd in memory, and blow life into them.
Egg-walking with qemu-nbd and kpartx
I wanted to retrieve a file from a VirtualBox VDI image for this blog post.
I followed these instructions and ended up here:
Once having used nbd0, only rebooting the system makes it possible to mount another image ... a little bit unpractical.
What happened was this:
# modprobe nbd # NOO! Don't *EVER* do that! # qemu-nbd -c /dev/nbd0 file.vdi # kpartx -d /dev/nbd0 # mount /dev/nbd0… EHI! Where's /dev/nbdpp1 ?? # qemu-nbd -d /dev/nbd0 # rmmod nbd rmmod: ERROR: Module nbd is in use # kpartx -d /dev/nbd0 read error, sector 0 llseek error llseek error llseek error # rmmod nbd rmmod: ERROR: Module nbd is in use # WHAT THE…
It turns out it's really modprobe nbd max_part=16, otherwise max_part
defaults to, uhm, zero? really? and kpartx cannot create device mappings
because there are not enough (as in, not even a single one) partition devices
available.
At this point, however, kpartx did create some mappings connected to, uhm, probably Ancient Beings from beyond spacetime, and because of those the device is in use and cannot be removed, and unmapping doesn't work either because the Ancient Beings from beyond spacetime are keeping the device busy by feeding on it.
I energized the pentacle and tried a desperate ritual of banishment:
# # Reconnect nbd0 to the vdi file to Restore the Balance # qemu-nbd --verbose -c /dev/nbd0 file.vdi # # This works now # kpartx -vd /dev/nbd0 del devmap : nbd0p5 del devmap : nbd0p2 del devmap : nbd0p1 # # This too, the Ancient Beings lie asleep yet again # modprobe nbd -r
At this point I managed to get my file, almost:
# modprobe nbd max_part=16 # qemu-nbd --verbose -c /dev/nbd0 file.vdi NBD device /dev/nbd0 is now connected to file.vdi # kpartx -va /dev/nbd0 add map nbd0p1 (254:12): 0 60260352 linear 43:0 2048 add map nbd0p2 (254:13): 0 2 linear 43:0 60264446 add map nbd0p5 (254:14): 0 2648064 linear 43:0 60264448 # mount /dev/nbd0p1 /mnt mount: /dev/nbd0p1 is already mounted or /mnt busy # # WHAT NOW?! # lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT … nbd0 43:0 0 30G 0 disk ├─nbd0p1 43:1 0 28.8G 0 part ├─nbd0p2 43:2 0 1K 0 part ├─nbd0p5 43:5 0 1.3G 0 part ├─nbd0p1 254:12 0 28.8G 0 part ├─nbd0p2 254:13 0 1K 0 part └─nbd0p5 254:14 0 1.3G 0 part # # WHAAAT?!! # kpartx -vd /dev/nbd0 del devmap : nbd0p5 del devmap : nbd0p2 del devmap : nbd0p1 # lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT … nbd0 43:0 0 30G 0 disk ├─nbd0p1 43:1 0 28.8G 0 part ├─nbd0p2 43:2 0 1K 0 part └─nbd0p5 43:5 0 1.3G 0 part # mount /dev/nbd0p1 /mnt # # I got my file, my preciouss file! # umount /mnt # kpartx -vd /dev/nbd0 # qemu-nbd -d /dev/nbd0 # rmmod nbd # # sit in a corner hugging my precious file and sobbing quietly
As can be seen from the multiple exclamation marks, those Ancient Beings from beyond spacetime did manage to have a bite on my sanity after all.
debian eng pdo swJessie live on UEFI systems
According to the Debian Wiki, you can't boot a Debian Live based on Jessie on a UEFI system:
UEFI support in live images At this point, UEFI support exists only in Debian's installation images. The accompanying live images do not have support for UEFI boot, as the live-build software used to generate them still does not include it. Hopefully the debian-live developers will add this important feature soon.
Some people really needed it, though, so I kept looking.
Here's a script that takes a Jessie Debian Live .iso file and the device name
for a USB pendrive, and gives you a pendrive that boots on UEFI:
#!/bin/sh # License: do what you want but it's not my fault, I told you not to. sh -ue ISO=${1:?"Usage: $0 file.iso usbdev"} DEV=${2:?"Usage: $0 file.iso usbdev"} parted -s $DEV mklabel gpt mkpart primary fat32 1 100% mkfs.vfat ${DEV}1 mount ${DEV}1 /mnt bsdtar -C /mnt -xf $ISO mkdir -p /mnt/efi/boot # Shell.efi comes from https://svn.code.sf.net/p/edk2/code/trunk/edk2/ShellBinPkg/UefiShell/X64/ cp Shell.efi /mnt/efi/boot/Bootx64.efi echo 'live\vmlinuz initrd=live\initrd.img append boot=live components' > /mnt/startup.nsh umount /mnt
Only use it if you really need it, though: Stretch will support this out of the box, and it's coming soon.
debian eng pdo swConscio dell'immagine di me
L'uomo in casa deve…, sennò lei se ne approfitta. Il bambino deve imparare che…, sennò se ne approfitta. La gente se ne approfitta. Si approfittano di te, non devono approfittarsi di te. Te ne approfitti, eh? Non dare subito la risposta semplice, pensaci su, cerca di meglio, guarda se c'era una domanda trabocchetto, non voler vincere facile, non essere pigro, fai uno sforzo, fai vedere che ci metti dell'impegno, non dargli soddisfazione, fatti valere. Tu hai visto un bel mondo. Devi… non puoi tirarti indietro ora, è importante, devi esserci, non puoi dire di no, non puoi deludere tutti. Non puoi essere come… i grassi, gli ingenui, i semplici, i creduloni, i brutti, quelli vestiti male, gli sfigati, quelli che…, quelli che non… Non puoi uscire con… i grassi, gli ingenui, i semplici, i creduloni, i brutti, quelli vestiti male, gli sfigati, quelli che…, quelli che non… Ama chi vuoi, ma non… i grassi, gli ingenui, i semplici, i creduloni, i brutti, quelli vestiti male, gli sfigati, quelli che…, quelli che non… O non usciremo con te, o non ti ameremo. Ho imparato a fare attenzione alle narrative, a controllare come viene percepito quello che dico, prima di parlare, prima di chiedere, prima di esistere in pubblico. A non desiderare, in compagnia di altri, quello che non bisogna fare, fino ad essere, in compagnia di altri, soltanto un altro.ita life
Gli altri
Gli Altri erano un mondo a parte, una massa insensata, con logiche sue, logiche oscure. Un mondo che a volte si interessava a me, travolgendomi, poi perdeva interesse e se ne andava. Lo dovevo tenere buono, per evitare di esserne travolto. Avevo paura di finire al centro dei suoi interessi. di diventare un suo hobby. "Non merito la tua attenzione, non ti chiedo niente, non mi metto in mostra, non ho bisogni, sto bene cosí, non causo problemi, ti do quello che chiedi, non ti disturbo, non guardarmi, non sono nessuno, non è me che stai cercando." Ho provato a chiedere: "lasciami stare"… "E perché? Come sei… Volevo solo chiederti… Volevo solo dirti… Volevo solo farti vedere… Volevo solo che tu… Dai, non fare cosí, stai al gioco! Non stare in un angolo! Dí qualcosa anche tu! Fammi divertire!" E allora gli davo quello che chiedeva finché non mi lasciava stare, ma non è me che stava cercando.ita life
Accident on the motorway
There was an accident on the motorway, luckily noone got seriously wounded, but a truckful of sugar and a truckful of cereals completely spilled on the motorway, and took some time to clean.
Vector Discordian Pope Cards
I like Discordian Pope cards.
I wanted to print a batch, but online I could only find low-quality .jpg
versions, so I took inkscape, used the low-quality as
a template grayed out in a background immutable layer, and redid them properly.
Here are the results:
Preview:
I release them under the WTFPL license: you can print them, redistribute them, and modify them at will.
The fonts I used are:
- Nimbus Roman, as found in Debian
- Nimbus Sans, as found in Debian
- Dearest by West Wind Fonts
Update: now available as a git repo
eng life pdoModena City Ramblers - Bella Ciao
Today is Liberation Day, and Bella Ciao will be sung a lot, remembering the Partisan movement.
Modena City Ramblers made a popular version.
The song originated before the second world war, as a song sung by mondine, women seasonally hired, or rather exploited, to work in flooded rice fields.
Here's a performance of the original version sung by Milva.
It is said that they were forbidden to talk during their work, so they sang instead, developing a peculiar singing style that could carry across the fields.
Here's Coro delle Mondine di Bentivoglio performing Son la Mondina, son la sfruttata in the original style.
eng songs