Re: [PATCH] blk-mq: move blk_mq_update_nr_hw_queues synchronize_rcu call

On Thu, Jun 18, 2020 at 07:30:22PM +0100, Giuliano Procida wrote:

This fixes the 4.9 backport commit f530afb974c2e82047bd6220303a2dbe30eff304 which was upstream commit f5bbbbe4d63577026f908a809f22f5fd5a90ea1f.

The upstream commit added a call to synchronize_rcu to _blk_mq_update_nr_hw_queues, just after freezing queues.

In the backport this landed (in blk_mq_update_nr_hw_queues instead), just after unfreezeing queues.

This commit moves the call to its intended place.

Fixes: f530afb974c2 ("blk-mq: sync the update nr_hw_queues with blk_mq_queue_tag_busy_iter") Signed-off-by: Giuliano Procida gprocida@google.com

Good catch! I've queued this and the 4.14 version.