On Thu, Apr 18, 2024 at 06:46:06PM +0200, Martin Wilck wrote: > > Why would we? It makes absolutly no sense to inherit these limits, > > the lower device will split anyway which is very much the point of > > the immutable bio_vec work. > > > > Sorry, I don't follow. With (request-based) dm-multipath on top of > SCSI, we hit the "over max size limit" condition in > blk_insert_cloned_request() [1], which will cause IO to fail at the dm > level. So at least in this configuration, it's crucial that the upper > device inherit the lower device's limits. Oh, indeed. Request based multipath is different from everyone else. I really wish we could spend the effort to convert it to bio based and remove this special case..
