[PATCH v2 3/3] nvme/multipath: fix stale ana state for namespaces just added by scan work

[Keith Busch]

On Mon, Sep 13, 2021 at 06:03:10PM +0200, Christoph Hellwig wrote:
> On Mon, Sep 13, 2021 at 09:30:23AM -0600, Anton Eidelman wrote:
> > Scan work initially adds new namespaces to ctrl->namespaces TAIL.
> > They make the list unordered temporarily until nvme_scan_work()
> > finally sorts the list.
> > 
> > Solution:
> > In order to preserve the way ctrl->namespaces is updated and sorted,
> > make nvme_update_ana_state() deal with the case where ctrl->namespaces
> > is not fully sorted and has new namespaces appended with potentially
> > lower nsids.
> > nvme_update_ana_state() keeps track of the nsid seen in the list,
> > detects the unsorted case (rare), and restarts scanning of desc->nsids.
> 
> Can we dust off the patch from Chaitanya to switch to an always sorted
> xarray instead of papering over this delayed sort?

Yeah, that's what I was going to say. :)