On Tue, Jul 24, 2018 at 09:07:03AM -0400, Mike Snitzer wrote: > True. We only ever support mapping the partitions ontop of > request-based multipath (via dm-linear volumes created by kpartx). > > > So, have you tested that request-based multipathing works on a > > partition _at all_? I'm not sure if partition mapping is done > > correctly here; we never remap the start of the request (nor bio, > > come to speak of it), so it looks as if we would be doing the wrong > > things here. > > > > Have you checked that partition remapping is done correctly? > > It clearly doesn't work. Not quite following why but... blk_insert_cloned_request seems to be missing a call to blk_partition_remap. Given that no one but dm-multipath uses this request clone insert helper, and people generally run multipath on the whole device this is a code path that is almost never exercised.
