On 01/10/2018 09:32 AM, Christoph Hellwig wrote: > On Tue, Jan 09, 2018 at 09:41:03PM -0500, Mike Snitzer wrote: >> Since I can remember DM has forced the block layer to allow the >> allocation and initialization of the request_queue to be distinct >> operations. Reason for this was block/genhd.c:add_disk() has required >> that the request_queue (and associated bdi) be tied to the gendisk >> before add_disk() is called -- because add_disk() also deals with >> exposing the request_queue via blk_register_queue(). > > Hmm. I don't even know how that could be safe given that the disk > is live and visible to userspace once added.. > We're getting an additional 'change' event once the tables are loaded and setup properly. That's not a problem, and in fact the DASD driver has the very same issue/feature/design. Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@xxxxxxx +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg)
