| === doko_ is now known as doko | ||
| === mythos_ is now known as mythos | ||
| === panda|x201 is now known as panda|w530 | ||
| jcz | I would like to install ubuntu core rootfs on SD card. Basically, im following this instructions: https://wiki.ubuntu.com/Core/InstallationExample but i have problems with chrooting and installing the kernel because it is an armhf rootfs. Any ideas how i could bypass this problem? | 10:12 |
|---|---|---|
| ogra_ | jcz, are you on a Ubuntu machine doing all this ? | 10:13 |
| jcz | ogra_: yes | 10:13 |
| ogra_ | then you can install qemu-user-static, that will set you up so you can chroot into arm cheroots (after copying one file into the chroot) | 10:13 |
| ogra_ | install it, then copy /usr/bin/qemu-arm-static to the /usr/bin inside the chroot dir ... then try ot chroot, it should work | 10:15 |
| jcz | ogra_: i will try it out now. BTW - how does this work with simply coping the binary? Does the package modify the chroot command to look for this file while chrooting? | 10:17 |
| ogra_ | no, the package installs a binfmt handler for th kernel ... the kernel notices the binary is for arm and wraps every such binary into a call to qemu-arm-static | 10:18 |
| jcz | ogra_: i think it worked :D thanks, really | 10:18 |
| ogra_ | (the wrapper has the path hardcoded, so to make sure it still works after chrooting, the binary needs to be in the same place) | 10:18 |
| jcz | ogra_: at least it managed to launch bash now | 10:19 |
| ogra_ | there is a qemu-debootstrap too ... that you can use to build such chroots from scratch | 10:19 |
| ogra_ | (that might be less cut down than ubuntu-core btw) | 10:20 |
| jcz | ogra_: oh, ill check it out (dont know what debootstrap is yet) | 10:21 |
| jcz | ogra_ i am kind of green in this stuff now | 10:21 |
| ogra_ | we all were once ;) | 10:22 |
| jcz | what is the difference between debootstrap, qemu-debootstrap and just unpacking ubuntu-core? debootstrap just downloads the image by itself and unpacks? | 10:35 |
| ogra_ | ubuntu-core is a tarball of a chroot that was built using debootstrap .... | 10:37 |
| jcz | and that qemu version? | 10:38 |
| ogra_ | debootstrap istself can only build for a binary compatible architecture (i.e. x86 on amd64 machines) ... | 10:38 |
| jcz | oh | 10:38 |
| ogra_ | to build a chroot it needs to chroot itself into the new root and configure the packages ... | 10:39 |
| jcz | so for arm i need qemu-debootstrap | 10:39 |
| ogra_ | so if you want a foreign arch you can use debootstrap in two steps (using the --foreign switch) ... in the arm case it would be that the first step is run on your PC and the second would have to run on your arm board | 10:39 |
| ogra_ | qemu-debootstrap now uses the above explained binfmt method to do both in one go | 10:40 |
| ogra_ | sand on your PC ... preventing you from having to do the second half on real hardware | 10:40 |
| ogra_ | s/sand/and/ | 10:41 |
| jcz | but still i guess it doesnt install the kernel? I need to do this with chrooting and running dpkg -i ? | 10:42 |
| ogra_ | right, debootstrap only builds root filesystems ... | 10:42 |
| ogra_ | for kernel and bootloader setup you have to take care yourself | 10:43 |
| ogra_ | (or use a prebuilt image if someone already took care of that step) | 10:43 |
| === chihchun is now known as chihchun_afk | ||
| === dewdgang_ is now known as dewdgang_frank | ||
| === dewdgang_frank is now known as frankie_ | ||
| === frankie_ is now known as frank1e | ||
| jcz | i have openwrt on my arm device. When i try to chroot to a ubuntu armhf rootfs on sdcard i get a segfault. Any ideas why would that be? Does it have any connection with using the hard float version? | 11:38 |
| jcz | i also tried booting ubuntu image on the device directly, and it failed.. | 11:39 |
| jcz | im using linux-image-3.8.0-34-generic armhf kernel | 11:39 |
| ogra_ | if you chroot into the sdcard, was it automounted ? | 11:41 |
| jcz | i mounted it manually | 11:41 |
| ogra_ | (note that udisks disables all binary execution on all automounted devices) | 11:41 |
| ogra_ | hmm, then it should just work | 11:42 |
| jcz | is there any way to see which program segfaults? | 11:42 |
| * ogra_ has no idea if the generic armhf kernel can run on openwrt though ... you would have to ask in #ubuntu-kernel | 11:42 | |
| jcz | just the chroot or i dont know - bash? | 11:42 |
| ogra_ | what is the exact error message ? | 11:42 |
| jcz | yes, just the segmentation fault | 11:43 |
| ogra_ | and is qemu-arm-static on the sd in /usr/bin/ ? | 11:43 |
| jcz | in the rootfs? | 11:43 |
| ogra_ | indeed | 11:43 |
| jcz | yes, it is there | 11:43 |
| ogra_ | if you chroot into the SD from the PC it needs to be there | 11:44 |
| ogra_ | and the SD needs to have the right mount options so that binaries can be executed on it | 11:44 |
| ogra_ | (if qou manually did a mount /dev/mmcblk* or /dev/sdX* on the cmdline, the defaults should usually be file) | 11:45 |
| jcz | i did: mkdir /mnt/root; mount /dev/mmcblk0p2 /mnt/root | 11:45 |
| jcz | and then chroot /mnt/root | 11:45 |
| ogra_ | that should work then | 11:46 |
| ogra_ | as long as qemu-arm-static is in /mnt/root/usr/bin/ | 11:46 |
| jcz | do i need to use the qemu on arm board? | 11:46 |
| jcz | it is already correct architecture | 11:47 |
| ogra_ | no, thats only for chrooting on the PC | 11:47 |
| ogra_ | on the board itself you should just get a proper bootloader and kernel setup and point the root= argument of the kernel commandline to the right device ... | 11:48 |
| jcz | when booting, i use parameters: console=ttyS0,115200 root=/dev/mmcblk0p2 rw rootfstype=ext4 noinitrd | 11:49 |
| jcz | and it just restarts the board after a while | 11:49 |
| jcz | the image is properly loaded into the memory from sd card, the checksums are okay | 11:49 |
| ogra_ | rootfstype should be autodetected by your kernel, it is obsolete ... you might want to add "rootwait" though so the system has enough time to initilize the SD card ... | 11:50 |
| jcz | that might be the case... ill check it out in a sec | 11:50 |
| ogra_ | are you sure that kernel works properly ? did you test it with some other rootfs before ? | 11:51 |
| * ogra_ would always start porting to some board with a known working kernel and bootloader | 11:51 | |
| jcz | i didnt boot that kernel yet. I think it should work because it is the ubuntu already compiled kernel. The bootloader works properly on the board and boots other stuff. | 11:53 |
| jcz | i downloaded it from ubuntu.packages.com | 11:53 |
| jcz | argh, adding rootwait didnt help | 11:55 |
| ogra_ | you are aware that the precompiled ubuntu arm kernels only work on a very limited amount of systems ? | 11:56 |
| jcz | hmm, not really :/ so you are suggesting that i need to compile the kernel myself? | 11:57 |
| ogra_ | (i think it is 4 or 5 boards for the generic kernel in 13.10, ask teh kernel team in #ubuntu-kernels which ones) | 11:57 |
| ogra_ | err | 11:57 |
| ogra_ | #ubuntu-kernel ... no "s" in the end | 11:57 |
| jcz | i dont see why it doesnt even print anything at all, just restarts | 12:14 |
| jcz | i suppose it could not work on the board, but at some point during boot or smth | 12:15 |
| ogra_ | well, i would try with a known working kernel first | 12:19 |
| ogra_ | (and bootloader) | 12:19 |
| === psivaa is now known as psivaa-lunch | ||
| === chrisccoulson is now known as notchrisccoulson | ||
| === psivaa-lunch is now known as psivaa | ||
| === notchrisccoulson is now known as chrisccoulson | ||
| === fly-away is now known as xaoser | ||
Generated by irclog2html.py 2.7 by Marius Gedminas - find it at mg.pov.lt!