From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A3264C43219 for ; Thu, 25 Apr 2019 14:39:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ACDF72081C for ; Thu, 25 Apr 2019 14:39:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="itxzsdnc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727325AbfDYOjG (ORCPT ); Thu, 25 Apr 2019 10:39:06 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:44874 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726102AbfDYOjF (ORCPT ); Thu, 25 Apr 2019 10:39:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Ox/A/M9f/YJNR/OkLo5ELVLHceNW1+cEY/T228JWq9Y=; b=itxzsdncAJJfxbIzDH3h8NzPR fTlTV7kliuirFPDQxRXM985hM+at1g/HkjfahIi1OLeEUCaf+KAVX02YgICFj+UNhHIUOpgPaLsiS YDBAzty13rzlzEOKjNy1EHM2hkjZdYRCcGSpDlJCNEuwVZ6WzpEzAlD/KBV01xSyj5Y9GaUoPJT01 +8xZAcOHZeFmcoDdzYD72TonxajqOfTLu4zinLJg/XzJawVjhnIszArCawp7iPVn0SZFHPQXnGAGE mmcsE7ie4qmHCf49khEqFd98M1+pdz+T1HqLHtxcT92hPPHgy3Q9wpUaP4GyY39eOrbBXwXxqz5Fe WZQDNK7ig==; Received: from hch by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1hJfWg-0000sH-RV; Thu, 25 Apr 2019 14:39:02 +0000 Date: Thu, 25 Apr 2019 07:39:02 -0700 From: Christoph Hellwig To: Aaron Ma Cc: Keith Busch , keith.busch@intel.com, axboe@fb.com, linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, Maxim Levitsky Subject: Re: [PATCH] nvme: determine the number of IO queues Message-ID: <20190425143902.GA30715@infradead.org> References: <1555510379-20199-1-git-send-email-aaron.ma@canonical.com> <096935354b16662eb481aeda1f48001ba489463c.camel@redhat.com> <20190418134820.GA7589@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.2 (2017-12-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 18, 2019 at 10:21:03PM +0800, Aaron Ma wrote: > > > On 4/18/19 9:48 PM, Keith Busch wrote: > > It does change the default behavior. If I have a degraded controller that > > can't do IO in a machine with 1000's of CPUs, I have to iterate this > > non-standard behavior 1000's of times before the drive is servicable > > again. We currenlty figure that out in just a single try. > > > > At least the quirks document *why* the driver is doing non-standard > > behavior. We do the IO queue quirks for Macbooks, for example. > > > > But why don't you file a bug report with the device vendor instead? Surely > > a firmware fix provides the best possible outcome, and would make this > > device work not only in all versions of Linux, but also every standard > > compliant driver for any OS. > > I will do it, no v2 for now. Honestly, unless this is a device shiping in a max market consumer product already I don't think we should work around this crap at all, given that this device has obviously never been tested at all. It really needs a firmware fix instead of a host workaround.