[dm-devel] [PATCH v4 10/20] libmultipath: indicate wwid failure in dm_addmap_create()

[Martin Wilck]

On Thu, 2018-04-12 at 13:33 -0500, Benjamin Marzinski wrote:
> On Wed, Apr 04, 2018 at 06:16:17PM +0200, Martin Wilck wrote:
> > dm_addmap_create() is where we actually try to set up a new
> > multipath map. Depending on the result, mark the wwid as
> > failed (or not), and re-trigger an uevent if necessary.
> > If a path changes from multipath to non-multipath, use an "add"
> > event to make sure LVM2 rules pick it up. Increase log level
> > of this event to 3.
> > 
> 
> By only looking at domap, we will miss instances of multipathd
> failing
> to create maps earlier in the process. This isn't necessarily wrong.
> It
> just means that we can't rely on checking
> /dev/shm/multipath/failed_wwids to definitively tell us whether
> multipathd has tried and failed to create the device.

Sorry, I can't follow you. Where else except in the 
domap->dm_addmap_create->dm_addmap() code path do we create maps?
I'm feeling stupid, I really can't see it.

Martin

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