On Tue, 2017-09-26 at 16:50 +0800, Ming Lei wrote: > If you don't consider to change mpath into block in .queue_rq() now, > please take this patch first, and I am sure this way is correct, and > even it can be thought as a fix.
As I explained earlier, it would be wrong to take this patch upstream without having tested and measured the alternative I had proposed first (https://www.spinics.net/lists/dm-devel/msg32282.html). My alternative handles SCSI hosts with multiple LUNs properly but the patch at the start of this e-mail thread not. Bart.