On 14/08/2019 13:06, Keith Busch wrote: > On Wed, Aug 14, 2019 at 07:28:36AM -0700, Guilherme G. Piccoli wrote: >>[...] > > The subsystem lifetime is not tied to a single controller's. Disconnect > the "first" controller in a multipathed subsystem with this patch, then > connect another controller from a different subsystem, and now you will > create naming collisions. >
Hi Keith, thanks for your clarification. Isn't the controller id unique? Could the new connected controller from a different subsystem have the same id? If you can give a rough example I appreciate. But given the above statement is a fact, what do you think of trying the ctrl->instance first and in case we have duplicity, fallback to subsystem ID allocator? Since the creation of subsystems is not a critical path, adding this small burden shouldn't be a huge penalty, and it'll help a lot with the huge amount of reports of "confusion" after the introduction of nvme multipathing, also it helps for the case I mentioned in the description, some multipath'ed controllers, some single ones. Cheers, Guilherme
