Enhancing 'autoinstall-user-data' with s390x specific device enablement

[Frank Heimes]

On s390x systems (IBM Z and LinuxONE) the s390x specific devices (or better ccw-devices) need to be enabled prior to their usage.
(This does _not_ apply to PCIe devices that the platform supports as well.)

Today this aspect of the special ccw-device enablement is not addressed in the 'autoinstall-user-data' file, which is created while doing a manual installation, but could be easily.

At the end of an interactive installation on a s390x system (or actually already right after the 'zDev' activation screen of subiquity) all s390x specific devices are known and can be obtained by:
$ lszdev --online
TYPE ID ON PERS NAMES
zfcp-host 0.0.e000 yes yes
zfcp-host 0.0.e100 yes yes
zfcp-lun 0.0.e000:0x50050763060b16b6:0x4026400300000000 yes yes sda sg0
zfcp-lun 0.0.e000:0x50050763061b16b6:0x4026400300000000 yes yes sdb sg1
zfcp-lun 0.0.e100:0x50050763060b16b6:0x4026400300000000 yes yes sdd sg3
zfcp-lun 0.0.e100:0x50050763061b16b6:0x4026400300000000 yes yes sdc sg2
qeth 0.0.c000:0.0.c001:0.0.c002 yes yes encc000
But this output can also be nicely filtered to just print the relevant device information like this:
$ lszdev --online --column ID --no-headings
0.0.e000
0.0.e100
0.0.e000:0x50050763060b16b6:0x4026400300000000
0.0.e000:0x50050763061b16b6:0x4026400300000000
0.0.e100:0x50050763060b16b6:0x4026400300000000
0.0.e100:0x50050763061b16b6:0x4026400300000000
0.0.c000:0.0.c001:0.0.c002

This is already the base for the device activation.
Enriching this information with the command that triggers the enablement ('chzdev --enable'):
$ for i in $(lszdev --online --column ID --no-headings); do echo chzdev -e $i; done
chzdev -e 0.0.e000
chzdev -e 0.0.e100
chzdev -e 0.0.e000:0x50050763060b16b6:0x4026400300000000
chzdev -e 0.0.e000:0x50050763061b16b6:0x4026400300000000
chzdev -e 0.0.e100:0x50050763060b16b6:0x4026400300000000
chzdev -e 0.0.e100:0x50050763061b16b6:0x4026400300000000
chzdev -e 0.0.c000:0.0.c001:0.0.c002
produces the list of commands that can be _directly_ added to the 'early-commands' section of the 'autoinstall-user-data' file.

Even if some devices get enabled using a different approach (for example using the boot kernels parm file or using the auto-conf option of a DPM machine), this doesn't hurt since it will be noticed and tolerated by the chzdev command:
$ for i in $(lszdev --online --column ID --no-headings); do chzdev -e $i; done
FCP device 0.0.e000 already configured
FCP device 0.0.e100 already configured
zFCP LUN 0.0.e000:0x50050763060b16b6:0x4026400300000000 already configured
zFCP LUN 0.0.e000:0x50050763061b16b6:0x4026400300000000 already configured
zFCP LUN 0.0.e100:0x50050763060b16b6:0x4026400300000000 already configured
zFCP LUN 0.0.e100:0x50050763061b16b6:0x4026400300000000 already configured
QETH device 0.0.c000:0.0.c001:0.0.c002 already configured
$ echo $?
0

[Frank Heimes (fheimes)]

I think work on that has already started:
https://github.com/canonical/subiquity/pull/800

[Michael Hudson-Doyle (mwhudson)]

That branch isn't going anywhere currently though :/ Do you agree with xnox that a more sophisticated schema is needed / desired?

[Frank Heimes (fheimes)]

I've directly commented on github:
https://github.com/canonical/subiquity/pull/800#issuecomment-927570424