CONFIG_NVME_MULTIPATH - Do we need this?

[John Meneghini]

At this point I think we are going to remove the module_param(multipath) and leave the KCONFIG option alone.

That should be a little less disruptive and we can always submit a separate patch to remove the KCONFIG option later.

Red Hat is currently testing this change internally and will submit a patch for consideration sometime next week.

Thanks,

/John

On 11/19/24 05:18, Nilay Shroff wrote:
> 
> 
> On 11/13/24 05:53, John Meneghini wrote:
>> Now that RHEL-10 beta has shipped we no longer support anything but native nvme multi-pathing and I'd like to do something about the multipath module parameter:
>>
>> bool multipath = true;
>> module_param(multipath, bool, 0444);
>> MODULE_PARM_DESC(multipath,
>>          "turn on native support for multiple controllers per subsystem");
>>
>> I'd like to remove this parameter from nvme_core/multipath.c. The fact is, setting nvme_core.multipath=N never worked in anything but RHEL and keeping it around only causes confusion.
>>
>> For that matter, I'd like to remove the CONFIG_NVME_MULTIPATH kconfig option altogether.
>>
>> Does anybody actually use this?
>>
>> # CONFIG_NVME_MULTIPATH is not set
>>
>> Do we actually support running nvme without multipath.c ?
>>
> Yes I think it's supported but I don't foresee any side effect of removing
> CONFIG_NVME_MULTIPATH except that the following blktests would require some updates:
> 
> nvme/033
> nvme/034
> nvme/035
> nvme/036
> nvme/037
> nvme/039
> 
> All above tests require CONFIG_NVME_MULTIPATH is unset. So if you're planning
> to get rid off this config option then we need to update above tests.
> 
> Thanks,
> --Nilay
> 
> 
>