Re: [Regression] Commit "nvme/pci: Use host managed power state for suspend" has problems

Rafael J. Wysocki
2019-07-31T22:33:35Z

On Thu, Aug 1, 2019 at 12:22 AM Keith Busch <kbusch@kernel.org> wrote:
>
> On Wed, Jul 31, 2019 at 11:25:51PM +0200, Rafael J. Wysocki wrote:
> >
> > A couple of remarks if you will.
> >
> > First, we don't know which case is the majority at this point. For
> > now, there is one example of each, but it may very well turn out that
> > the SK Hynix BC501 above needs to be quirked.
> >
> > Second, the reference here really is 5.2, so if there are any systems
> > that are not better off with 5.3-rc than they were with 5.2, well, we
> > have not made progress. However, if there are systems that are worse
> > off with 5.3, that's bad. In the face of the latest findings the only
> > way to avoid that is to be backwards compatible with 5.2 and that's
> > where my patch is going. That cannot be achieved by quirking all
> > cases that are reported as "bad", because there still may be
> > unreported ones.
>
> I have to agree. I think your proposal may allow PCI D3cold,

Yes, it may.

> In which case we do need to reintroduce the HMB handling.

Right.