CONFIG_NVME_MULTIPATH - Do we need this?

[Nilay Shroff]

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