Re: [PATCH v5 2/3] hw/s390x: add Control-Program Identification to QOM

[Shalini Chellathurai Saroja <shalini@linux.ibm.com>]

On 2025-06-13 11:59, Thomas Huth wrote:
> On 03/06/2025 15.56, Shalini Chellathurai Saroja wrote:
>> Add Control-Program Identification (CPI) data to the QEMU Object
>> Model (QOM), along with the timestamp in which the data was received
>> as shown below.
> ...
>> diff --git a/qapi/machine.json b/qapi/machine.json
>> index 5373e1368c..1f2db68032 100644
>> --- a/qapi/machine.json
>> +++ b/qapi/machine.json
>> @@ -2279,3 +2279,61 @@
>>   # Since: 1.2
>>   ##
>>   { 'command': 'query-cpu-definitions', 'returns': 
>> ['CpuDefinitionInfo'] }
>> +
>> +##
>> +# @S390ControlProgramId:
>> +#
>> +# Control-program identifiers provide data about the guest operating 
>> system.
>> +# The control-program identifiers are: system type, system name, 
>> system level
>> +# and sysplex name.
>> +#
>> +# In Linux, all the control-program identifiers are user 
>> configurable. The
>> +# system type, system name, and sysplex name use EBCDIC characters 
>> from
>> +# this set: capital A-Z, 0-9, $, @, #, and blank.  In Linux, the 
>> system type,
>> +# system name and sysplex name are arbitrary free-form texts.
>> +#
>> +# In Linux, the 8-byte hexadecimal system-level has the format
>> +# 0x<a><b><cc><dd><eeee><ff><gg><hh>, where:
>> +# <a>: is one hexadecimal byte, its most significant bit indicates 
>> hypervisor
>> +# use
> 
>  Hi Shalini!
> 
> While testing the patches, the above description caused some headache
> for me, but I think it's simply typo here: This is not a hexadecimal
> byte, it's just a nibble / 4-bit digit for this <a>, right? Could you
> please fix the description in the next version of the patch series,
> please?


Hello Thomas,
Yes, that is correct. <a> is a 4-bit digit and not a byte. I will 
correct this
in the next version. Thank you very much.

> 
>  Thanks,
>   Thomas
> 
> 
>> +# <b>: is one digit that represents Linux distributions as follows
>> +# 0: generic Linux
>> +# 1: Red Hat Enterprise Linux
>> +# 2: SUSE Linux Enterprise Server
>> +# 3: Canonical Ubuntu
>> +# 4: Fedora
>> +# 5: openSUSE Leap
>> +# 6: Debian GNU/Linux
>> +# 7: Red Hat Enterprise Linux CoreOS
>> +# <cc>: are two digits for a distribution-specific encoding of the 
>> major version
>> +# of the distribution
>> +# <dd>: are two digits for a distribution-specific encoding of the 
>> minor version
>> +# of the distribution
>> +# <eeee>: are four digits for the patch level of the distribution
>> +# <ff>: are two digits for the major version of the kernel
>> +# <gg>: are two digits for the minor version of the kernel
>> +# <hh>: are two digits for the stable version of the kernel
>> +# (e.g. 74872343805430528, when converted to hex is 
>> 0x010a000000060b00). On
>> +# machines prior to z16, some of the values are not available to 
>> display.
>> +#
>> +# Sysplex refers to a cluster of logical partitions that communicates 
>> and
>> +# co-operates with each other.
>> +#
>> +# @system-type: operating system (e.g. "LINUX   ")
>> +#
>> +# @system-name: user configurable name of the VM (e.g. "TESTVM  ")
>> +#
>> +# @system-level: distribution and kernel version in Linux
>> +#
>> +# @sysplex-name: sysplex which the VM belongs to, if any (e.g. "PLEX 
>> ")
>> +#
>> +# @timestamp: latest update of CPI data in nanoseconds since the UNIX 
>> EPOCH
>> +#
>> +# Since: 10.1
>> +##
>> +{ 'struct': 'S390ControlProgramId', 'data': {
>> +     'system-type': 'str',
>> +     'system-name': 'str',
>> +     'system-level': 'uint64',
>> +     'sysplex-name': 'str',
>> +     'timestamp': 'uint64' } }

-- 
Mit freundlichen Grüßen / Kind regards
Shalini Chellathurai Saroja
Software Developer
Linux on IBM Z & KVM Development
IBM Deutschland Research & Development GmbH
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