On Thu, Nov 15, 2018 at 11:30:15AM -0600, Bjorn Helgaas wrote: > > But I guess you have to do this anyway just to add the vendor/device > ID to the driver, so maybe this isn't a big deal to you. If you can > do a quirk like this in the driver, it would be invisible to me and I > wouldn't care. I just don't want to deal with ongoing tweaks like > this in the PCI core :) No, NVMe is a spec with a class code, and a specification that is vendor independent. NVMe devices declare invididual features based on common fields. APST is an optional feature with all kinds of parameters, but there is absolutely no language that a host should not put the device into D3 mode if APST is supported anywhere in the NVMe spec, and such behavior is also rather counter intuitive. If SK Hynix thinks this is sensible behavior they should bring it up in the NVMe technical working group. I've pinged a contact there to see what this whole story is about.
