[PATCH 3/3] nvme: wwid_show: copy hex string verbatim

[Martin Wilck]

On Fri, 2017-07-14 at 14:30 +0200, Christoph Hellwig wrote:
> On Fri, Jul 14, 2017 at 11:58:16AM +0200, Martin Wilck wrote:
> > If this is what you think, you must also NAK my patch 2/3, because
> > stripping the 0-bytes also changes how the WWID is presented to
> > user
> > space. For example
> 
> True.  Although that only really is a fix for buggy controllers,
> and should not affect the PCIe controllers (for which a compliance
> test for this exists, unfortunately that doesn't work for fabrics).

Is that a NAK, or not?

> > User space that relies on the string in the first format would
> > break
> > already with 2/3. However, multipath, which is probably the main
> > consumer of the WWID for practical purposes, can't handle the
> > overlong
> > format anyway (I'm preparing a patch series to fix that).
> 
> We'll handle multipath in NVMe and the kernel itself, so we really
> should not be worried about dm-multipath here, which is the wrong
> thing to do for NVMe.

"We will"? People are (trying to) use NVMe with multipath today, and
they use dm-multipath and multipathd for that. Maybe that'll change
some day, but not too soon, I believe.

Regards
Martin

-- 
Dr. Martin Wilck <mwilck at suse.com>, Tel. +49 (0)911 74053 2107
SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton
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