Re: [PATCH v4] powerpc/pseries: read the lpar name from the firmware

From: Nathan Lynch
Date: Wed Jan 05 2022 - 18:20:18 EST


Laurent Dufour <ldufour@xxxxxxxxxxxxx> writes:
> On 07/12/2021, 18:11:09, Laurent Dufour wrote:
>> The LPAR name may be changed after the LPAR has been started in the HMC.
>> In that case lparstat command is not reporting the updated value because it
>> reads it from the device tree which is read at boot time.
>>
>> However this value could be read from RTAS.
>>
>> Adding this value in the /proc/powerpc/lparcfg output allows to read the
>> updated value.
>
> Do you consider taking that patch soon?

This version prints an error on non-PowerVM guests the first time
lparcfg is read.

And I still contend that having this function fall back to reporting the
partition name in the DT would provide a beneficial consistency in the
user-facing API, allowing programs to avoid hypervisor-specific branches
in their code. I don't understand the resistance I've encountered here.
The fallback I'm suggesting (a root node property lookup) is certainly
not more complex than the RTAS call sequence you've already implemented.