Re: [PATCH RFC] scsi: ufs: Disable blk-mq for now

From: Christoph Hellwig
Date: Thu Sep 20 2018 - 02:58:06 EST


On Fri, Sep 14, 2018 at 09:52:38AM +0800, Ming Lei wrote:
> However, in previous discussion, it is strongly objected to use
> per-driver/device .use_blk_mq switch, so not sure if this way can
> be accepted.

I don't like the per-driver switch as module_parameter at all and
we should never do that. We had some exceptions for drivers to force
blk_mq (e.g. virtio), and given that I don't think we'll solve the
blk-mq runtime-pm issue for 4.19 and also don't want to revert the
default I think this patch is the best compromise for 4.19, with
a revert in 4.20 once we have runtime-pm for blk-mq.

So:

Acked-by: Christoph Hellwig <hch@xxxxxx>