On Thu, May 10, 2018 at 03:44:41PM -0600, Keith Busch wrote: > On Fri, May 11, 2018 at 05:24:46AM +0800, Ming Lei wrote: > > Could you share me the link? > > The diff was in this reply here: > > http://lists.infradead.org/pipermail/linux-nvme/2018-April/017019.html > > > Firstly, the previous nvme_sync_queues() won't work reliably, so this > > patch introduces blk_unquiesce_timeout() and blk_quiesce_timeout() for > > this purpose. > > > > Secondly, I remembered that you only call nvme_sync_queues() at the > > entry of nvme_reset_work(), but timeout(either admin or normal IO) > > can happen again during resetting, that is another race addressed by > > this patchset, but can't cover by your proposal. > > I sync the queues at the beginning because it ensures there is not > a single in flight request for the entire controller (all namespaces > plus admin queue) before transitioning to the connecting state. > > If a command times out during connecting state, we go to the dead state. Actually, it is hang forever in blk_mq_freeze_queue_wait() from nvme_reset_dev(), not a dead state of controller. Thanks, Ming
