What were you trying to do that didn't work?

I found that the kernel rd.dasd option sets the DASD disk up as both eckd and fba, whereas using chzdev to enable it later will only set it up as eckd.
The double set up eckd and fba leads to errors when handling the state of the disk.

What is the impact of this issue to you?

It broke a test because it didn't expect an error. Functionally I think the system works well for our purposes, that is r/w from Linux OS after formatting it with

dasdfmt -b 4096...

with cdl (default).

Please provide the package NVR for which the bug is seen:

s390utils-2.36.0-2.el10.s390x

How reproducible is this bug?:

100%

Steps to reproduce

1. Install a system on an LPAR with kernel parameter

   rd.dasd = 0.0.4020

2. Log into the system
3. Run

   # chzdev -e 0.0.4020

Expected results

# chzdev -e 0.0.4020
ECKD DASD 0.0.4020 already configured
root@rdu-z16-l29:~# echo $?
0

Actual results

# chzdev -e 0.0.4020
ECKD DASD 0.0.4020 already configured
FBA DASD 0.0.4020 configure failed
    Error: Trying to configure ECKD DASD 0.0.4020 as FBA DASD
# echo $?
5

Additional info

1. I don't know what the expected behavior is. Having bith FBA and ECKD looks wrong.
   • UPDATE: I now believe this is really wrong because if I put both fba and eckd rules into the udev rules folder and try to enable I get also this error

      Error: Trying to configure ECKD DASD 0.0.4021 as FBA DASD

2. Attaching more information (commands executed, available udev rules etc.)