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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 84698C433EF for ; Thu, 10 Feb 2022 11:14:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240676AbiBJLOz (ORCPT ); Thu, 10 Feb 2022 06:14:55 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:48692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240674AbiBJLOz (ORCPT ); Thu, 10 Feb 2022 06:14:55 -0500 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9C010CCA for ; Thu, 10 Feb 2022 03:14:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1644491696; x=1676027696; h=date:from:to:cc:subject:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=xBPRSyhyR4MWqAybTeGLySCbhYmmr6xdI+ZMnIpDIUA=; b=DEMA6YrR39IK9FUabRulRl1vLfKi7w/nvzuEt4EFNrwrY0DudTEJr3PV QVSzk5MSKCmkPej/csnaGr+AOCnvPlEG01wzFOxf/zH4YdYUmT6tzoDlC bnFqhN6TJAyqrBt3Z5owmaMP7HBT85N85hVYO4EY96gAA0z0JldN3ekC7 rrPiiKyFaGeN3MSgDyOo88XIiV2xepzBTOoh022y41svXJo8eU/50ekhg +we1KtL2kgo1aBQhkm9XuL/Yn0MkDYkikeOc35RFSV0kaOC0e1fHAGSc3 8B+N7gRTUQc6LBYyZgStkxF3hVss5OqOPQI8FEi2NBka/lnCP9DBheDnr A==; X-IronPort-AV: E=McAfee;i="6200,9189,10253"; a="274016367" X-IronPort-AV: E=Sophos;i="5.88,358,1635231600"; d="scan'208";a="274016367" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Feb 2022 03:14:55 -0800 X-IronPort-AV: E=Sophos;i="5.88,358,1635231600"; d="scan'208";a="541565333" Received: from bkucman-mobl.ger.corp.intel.com (HELO localhost) ([10.249.141.65]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Feb 2022 03:14:49 -0800 Date: Thu, 10 Feb 2022 12:14:44 +0100 From: Blazej Kucman To: Bjorn Helgaas Cc: Nirmal Patel , Kai-Heng Feng , Mariusz Tkaczyk , linux-pci@vger.kernel.org, Blazej Kucman , Hans de Goede , Lukas Wunner , Naveen Naidu , Keith Busch , Jonathan Derrick Subject: Re: [Bug 215525] New: HotPlug does not work on upstream kernel 5.17.0-rc1 Message-ID: <20220210121444.0000255f@linux.intel.com> In-Reply-To: <20220209210218.GA587489@bhelgaas> References: <20220209144102.0000143e@linux.intel.com> <20220209210218.GA587489@bhelgaas> X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.29; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, 9 Feb 2022 15:02:18 -0600 Bjorn Helgaas wrote: > On Wed, Feb 09, 2022 at 02:41:02PM +0100, Blazej Kucman wrote: > > On Thu, 3 Feb 2022 09:58:04 -0600 > > Bjorn Helgaas wrote: > > > > Why were you testing with "pci=nommconf"? Do you think anybody > > > uses that with VMD and NVMe? > > > > It was added long time ago when it was useful. > > I'm curious about why it was useful. It suggests a possible MMCONFIG > issue in firmware or in Linux. If it was a Linux issue, ideally we > would fix that. If it's a firmware issue, ideally we would work > around it or automatically turn on "pci=nommconf" so the user wouldn't > have to figure that out. > The parameter was added many years ago (project has more than 10 years) and I don't know the reason. Probably it was useful on pre-production platforms, for software validation. It was added to our internal BKMs. It didn't cause any real issue in our workflow until now. Unfortunately, I'm unable to answer more precisely. We scheduled steps to remove it definitely from our work environment. > > Bugzilla report can be closed if you don't consider it as > > regression. > > OK, I closed it with the details. I'm not entirely convinced that > 04b12ef163d1 ("PCI: vmd: Honor ACPI _OSC on PCIe features") was the > right thing, but I'll pursue that elsewhere. > > Thanks for your patience in working through this, and sorry for the > hassle it caused you. > > Bjorn Thanks, Blazej