[PATCH 06/17] block: introduce GENHD_FL_HIDDEN

[Christoph Hellwig]

On Tue, Oct 24, 2017 at 05:40:00PM -0400, Mike Snitzer wrote:
> Having the NVme driver go to such lengths to hide its resources from
> upper layers is certainly the work of an evil genius experiencing some
> serious territorial issues.  Not sugar-coating it.. you wouldn't.

I'm pretty surre Hannes will appreciate being called an evil genius :)

> I kept meaning to reply to your earlier iterations on this series to
> ask: can we please get a CONFIG_NVME_MULTIPATHING knob to make it so
> that the NVMe driver doesn't implicitly consume (and hide) all
> per-controler devices?

I thought about adding it, but mostly for a different reason: it's
quite a bit of code, and we now start to see NVMe in deeply embedded
contexts, e.g. the latest Compact Flash spec is based on NVMe, so it
might be a good idea to give people a chance to avoid the overhead.

> Ah well.  There is only one correct way to do NVMe multipathing after
> all right?

I don't think you'll get very useful results, even if you try.  But I
guess we'll just have to tell people to use SuSE if they want NVMe
multipathing to work then :)