Commit Graph

7 Commits

Author SHA1 Message Date
Michael Shigorin
f293239d5b build-vm: try system tar2fs first
It's at least removing the very obvious user->root
attack through (maliciously) modifying bin/tar2fs
and waiting for it to be run; if mkimage-profiles
is installed system-wide as a package, the script
from /usr/share/mkimage-profiles will be tried so
those willing to allow vm/* build to themselves
can provide for a passwordless sudo (as described
in doc/vm.txt) to run a root-only writable script,
not user-writable.

Still not perfect but a step away from the abyss.
2016-11-07 19:47:53 +03:00
Michael Shigorin
d7689f30c7 tar2vm: rewrote as tar2fs
Overview of the changes:
- ARM support: separate ext2 /boot, no LILO
- avoid race condition with devmapper
- trap ERR so that -e in shebang doesn't result in extra cleanup hassle
- configurable root filesystem type (ext4 by default)
- jumps through parted hoops

Details:

1. LILO is x86-specific while the rest of the script can be used
   to prepare e.g. Marvell ArmadaXP or CuBox images; we can generally
   count on uboot supporting ext2 for relatively sane platforms but
   not ext4 that would be a better root filesystem performance-wise.

2. Apparently /dev/mapper/loopXpY can be still missing at the time
   when kpartx returns and pop up a bit later... sit there, wait
   and check for it.

3. If something went wrong with any command of the script it would bail out
   due to -e in shebang; it is now better to clean up the loopback device
   and its mappings in this situation either.

4. One size doesn't fit all, really.

5. The parted sizing was sloppy as in broken, now it's just half insane.
   Someone's decision to stick units and auto-alignment knobs into
   a single one was apparently hilarious...

   http://www.gnu.org/software/parted/manual/parted.html#unit

Manual loop/dm cleanup is described in documentation just in case.

/boot size meter is suboptimal in terms of additional I/O incurred,
will be most likely rewritten to make use of advance "du -s".
2013-06-17 19:29:11 +04:00
Michael Shigorin
5b21100bed README update
These have been proofread somewhat to correspond
to the current state of affairs; a missing one
was added for fonts feature.
2013-06-10 19:43:31 +04:00
Mike Radyuk
85217cd11d added asciidoc support 2012-10-31 21:22:06 +02:00
Michael Shigorin
eb3df648a2 minor documentation facelift
A few more items were asking for some attention.

In particular, build examples should start with
the most basic, error-proof and quick targets.
2012-08-11 22:56:41 +03:00
Michael Shigorin
8a04d9b656 initial specific VM formats support
Raw disk images are convenient and universal
but there are custom formats like Qemu's qcow2
providing additional features, e.g. copy-on-write
or space savings.  All of this ultimately belongs
to mkimage but in the mean time has been implemented
here as well.
2012-06-25 19:29:38 +03:00
Michael Shigorin
75f7c62bd1 initial build-vm feature
Yes, mkimage-profiles is now able to build VM disk images.
So far the support is pretty basic:

- a single hard drive image with a single partition/FS
- only stock root password is configurable
- LILO is hardwired as a bootloader

The resulting images tend to boot under qemu/kvm though.

Please see doc/vm.txt for the warning regarding additional
privileges and setup required.  This was started back in
February but I still hoped to avoid sudo/privileged helper
(and libguestfs is almost as undistributable as can be)...

Thanks:

- http://blog.quinthar.com/2008/07/building-1gb-bootable-qemu-image-using.html
- Alexey Morarash who reworked that as https://github.com/tuxofil/linsygen
- led@, legion@, vitty@, aen@ for providing advice and inspiration
2012-06-18 21:56:46 +03:00