Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S940927AbdDTDKH (ORCPT ); Wed, 19 Apr 2017 23:10:07 -0400 Received: from mail-io0-f182.google.com ([209.85.223.182]:34681 "EHLO mail-io0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S940517AbdDTDKE (ORCPT ); Wed, 19 Apr 2017 23:10:04 -0400 Date: Wed, 19 Apr 2017 21:10:00 -0600 From: Jens Axboe To: Andy Lutomirski Cc: "linux-kernel@vger.kernel.org" , Kai-Heng Feng , linux-nvme@lists.infradead.org, Christoph Hellwig , Sagi Grimberg , Keith Busch Subject: Re: [PATCH 0/5] nvme APST fixes/improvements for 4.11 Message-ID: <20170420030959.GC23085@kernel.dk> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1339 Lines: 32 On Wed, Apr 19 2017, Andy Lutomirski wrote: > Sorry for waiting so long for this. I was waiting for feedback from > Samsung, but they haven't root-caused the issue yet, and I should > have just done this from the beginning. > > This series makes APST more debuggable and updates the quirk list. > The quirks I'm aware of are: > > - Samsung 950 series SSDs in Dell XPS 15 9550 and Precision 5510 > laptops (which are essentially the same laptop) can lose their > PCIe link if they're allowed to use the deepest APST state. > Samsung engineers have an affected system and are working on > it. The same exact SSDs in other machines (even an XPS 13) > seem to work fine. > > - One Toshiba device malfunctions if APST is used at all. You need to split this series in two, patches 1-3 can wait. For 4.11, all we need to do is turn off APST on any device that potentially has this problem. > One thing that improves my confidence that there aren't too many > more problems with APST is that Ubuntu has backported APST to Zesty, > so it's already gotten a bit of testing in a widely used (if very > new) release. Honestly, I think the best path for 4.11 is to turn off APST by default, make it opt-in instead. I don't share your optimism here, as I made clear back from before we even merged this feature. -- Jens Axboe