On Fri, Mar 31, 2017 at 11:59:24AM -0700, Omar Sandoval wrote: > From: Omar Sandoval <[email protected]> > > blk_mq_update_nr_hw_queues() used to remap hardware queues, which is the > behavior that drivers expect. However, commit 4e68a011428a changed > blk_mq_queue_reinit() to not remap queues for the case of CPU > hotplugging, inadvertently making blk_mq_update_nr_hw_queues() not remap > queues as well. This breaks, for example, NBD's multi-connection mode, > leaving the added hardware queues unused. Fix it by making > blk_mq_queue_reinit() optionally remap queues, which we do when updating > the number of hardware queues but not when hotplugging. > > Fixes: 4e68a011428a ("blk-mq: don't redistribute hardware queues on a CPU > hotplug event") > Signed-off-by: Omar Sandoval <[email protected]> > --- > The only callers of blk_mq_update_nr_hw_queues() are nbd and nbd. I *think* > nbd_dev_add() also wants this remap behavior.
Uh, I meant nbd and nvme, and nvme_dev_add().
