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=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 643F6C63798 for ; Tue, 17 Nov 2020 09:21:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E728C24671 for ; Tue, 17 Nov 2020 09:21:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="DwBmeWJS"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="YCVL+0Qr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727285AbgKQJV4 (ORCPT ); Tue, 17 Nov 2020 04:21:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50712 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726561AbgKQJVz (ORCPT ); Tue, 17 Nov 2020 04:21:55 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 84ACCC0613CF; Tue, 17 Nov 2020 01:21:55 -0800 (PST) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1605604913; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=+oNN0MQgkiBnCbtfwugoj2ueCMN1m2mxEsnINrDLEe0=; b=DwBmeWJShTfSxI7/bv9yMVNbyXuplY6dNWaJqhWyEBj0NEoUnDzm/Q61zBRx/jvfVqMab3 YqSSqciJOklmsPQhLhvFcAhDaCgdtLjlgDx1WVoEJhofYrTb+HZOhHdBmFYZ8sOC2J+3rF kkEshToFTkEciOfblmWCrEZp5P6IbtwlfRxWHlsTJbeLlyWYtXZ7SdaRZeP8Ae+vxzSOqK eStnMibR6Ryujt1YDKfPzB2cupuDgeXiLMpjrk89EkPjUsUGpsAGsIueuBeEINhXacrsmY QdeJkh0tBpaCWJVw6wHbr0zQo5UbpJ4Qszu9RndP91TowUjpuEanGAb23BvW1w== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1605604913; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=+oNN0MQgkiBnCbtfwugoj2ueCMN1m2mxEsnINrDLEe0=; b=YCVL+0Qrok4yb6+AmGU6uun36CXW4zeVISlAXjUYay+MYF25xqVx1q5xsECe4BULShPhcB gQiiXXhWd1DZjrAg== To: "Tian\, Kevin" , Jason Gunthorpe Cc: "Raj\, Ashok" , Christoph Hellwig , "Wilk\, Konrad" , "Williams\, Dan J" , "Jiang\, Dave" , Bjorn Helgaas , "vkoul\@kernel.org" , "Dey\, Megha" , "maz\@kernel.org" , "bhelgaas\@google.com" , "alex.williamson\@redhat.com" , "Pan\, Jacob jun" , "Liu\, Yi L" , "Lu\, Baolu" , "Kumar\, Sanjay K" , "Luck\, Tony" , "kwankhede\@nvidia.com" , "eric.auger\@redhat.com" , "parav\@mellanox.com" , "rafael\@kernel.org" , "netanelg\@mellanox.com" , "shahafs\@mellanox.com" , "yan.y.zhao\@linux.intel.com" , "pbonzini\@redhat.com" , "Ortiz\, Samuel" , "Hossain\, Mona" , "dmaengine\@vger.kernel.org" , "linux-kernel\@vger.kernel.org" , "linux-pci\@vger.kernel.org" , "kvm\@vger.kernel.org" Subject: RE: [PATCH v4 06/17] PCI: add SIOV and IMS capability detection In-Reply-To: References: <877dqqmc2h.fsf@nanos.tec.linutronix.de> <20201114103430.GA9810@infradead.org> <20201114211837.GB12197@araj-mobl1.jf.intel.com> <877dqmamjl.fsf@nanos.tec.linutronix.de> <20201115193156.GB14750@araj-mobl1.jf.intel.com> <875z665kz4.fsf@nanos.tec.linutronix.de> <20201116002232.GA2440@araj-mobl1.jf.intel.com> <20201116154635.GK917484@nvidia.com> <87y2j1xk1a.fsf@nanos.tec.linutronix.de> <20201116180241.GP917484@nvidia.com> Date: Tue, 17 Nov 2020 10:21:52 +0100 Message-ID: <875z64xrrj.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Mon, Nov 16 2020 at 23:51, Kevin Tian wrote: >> From: Jason Gunthorpe > btw Jason/Thomas, how do you think about the proposal down in this > thread (ims=[auto|on|off])? Does it sound a good tradeoff to move forward? What does it solve? It defaults to auto and then you still need to solve the problem of figuring out whether it's safe to use it or not. The command line option is not a solution per se. It's the last resort when the logic which decides whether IMS can be used or not fails to do the right thing. Nothing more. We clearly have outlined what needs to be done and you can come up with as many magic bullets you want, they won't make the real problems go away. Thanks, tglx