Support LUKS devices when using guestfish to inject ignition

[Prashanth684]

Add support for recognizing LUKS filesystem when setting up ignition.
While not necessary for x86 because it uses fw_cfg, ppc64 and s390x use guestfish
and need this change for kola tests to run.

[Prashanth684]

Could i get some reviews for this please ? and a lgtm hopefully ? :)

[jlebon]

Would be good to link to the analogous coreos-assembler change in the commit message: coreos/coreos-assembler#826.

One thing here, do we need to bump memory here as well? https://github.com/coreos/coreos-assembler/pull/826/files#diff-b67c90828c71ffa6aaa6454fa26aefa4R9-R15

[Prashanth684]

Would be good to link to the analogous coreos-assembler change in the commit message: coreos/coreos-assembler#826.

One thing here, do we need to bump memory here as well? https://github.com/coreos/coreos-assembler/pull/826/files#diff-b67c90828c71ffa6aaa6454fa26aefa4R9-R15

Will add the reference to the commit. I am not sure about the memory increase. I was able to run the kola tests without that change and seemed to work fine. @cgwalters is the memory increase for guestfs needed for the kola tests?

[cgwalters]

This seems OK to me, but I think it'd be simpler to just stop mounting the rootfs - we don't need it to inject Ignition into /boot right?

[tuan-hoang1]

This seems OK to me, but I think it'd be simpler to just stop mounting the rootfs - we don't need it to inject Ignition into /boot right?

Second this. So we can just remove the rootfs mounting after all - /boot is all we need.

[Prashanth684]

This seems OK to me, but I think it'd be simpler to just stop mounting the rootfs - we don't need it to inject Ignition into /boot right?

Second this. So we can just remove the rootfs mounting after all - /boot is all we need.

Yes. we could mount /boot using the guestfish debug shell, but one roadblock I hit was a way to upload a file to the partition in the debug shell. I am not a guestfish expert by any means so if someone knows of a way to do this that would be great.

[tuan-hoang1]

Using guestfish's mount command with boot partition (/dev/sda1) being as / instead of /boot if you don't want to mount rootfs (/dev/sda4) at /. Yeah it looks a little bit misleading but works:

guestfish --remote -- mount /dev/sda1 /
guestfish --remote -- mkdir-p /ignition
guestfish --remote -- upload ign.conf /ignition/ign.conf

Thinking on how to do guestfish debug sh in a nice way if you don't want above solution.

[Prashanth684]

Using guestfish's mount command with boot partition (/dev/sda1) being as / instead of /boot if you don't want to mount rootfs (/dev/sda4) at /. Yeah it looks a little bit misleading but works:

guestfish --remote -- mount /dev/sda1 /
guestfish --remote -- mkdir-p /ignition
guestfish --remote -- upload ign.conf /ignition/ign.conf

Thinking on how to do guestfish debug sh in a nice way if you don't want above solution.

i think this is much better. It is misleading in the sense that we are not putting it in "/", but it is a cleaner solution. i will close this PR and open a new one. thanks @tuan-hoang1 !

[Prashanth684]

opened #1124.