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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 6F2DCC433E1 for ; Tue, 30 Jun 2020 15:38:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4FD3A2074F for ; Tue, 30 Jun 2020 15:38:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593531510; bh=+mq7WcFXbYo5431aLEmBieudqWsKg/kt/fvcWMZkCBE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=nwnJrcHw7NEj8UjUMcshstv9wk90nyVITTCS7v4x/Yq/andvHK/iQTG5cXWP4TsNz 4OMtIbx4ckJ5jZjkfno18xgyU8S2rG3Renssu/Vlmym7x7mmGb46tUYV6EnasAqgGW wSEapDdwce3dXG0ZuZl+1QqES8coY4Bvss+yBpog= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389441AbgF3Pi3 (ORCPT ); Tue, 30 Jun 2020 11:38:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:33664 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731107AbgF3Pi3 (ORCPT ); Tue, 30 Jun 2020 11:38:29 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EC25A20675; Tue, 30 Jun 2020 15:38:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593531508; bh=+mq7WcFXbYo5431aLEmBieudqWsKg/kt/fvcWMZkCBE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Bl5RxFhCCwtZ5oZDGw16ns2h6Q1i3BvDgAiiZajr1R4bo3LNxd92zGKQulajPnAgr r+LDhITZ9t4UD+Arr3ExbqZRI1I7z4PJOV36rG+wNmngm6kE6gmcaxGmW6D7xP69RV T0U12bR/14EoCs2+2EM2angdXKN5GkhIQdYlIyCI= Date: Tue, 30 Jun 2020 17:38:16 +0200 From: Greg Kroah-Hartman To: "Rafael J. Wysocki" Cc: Rajat Jain , Heikki Krogerus , David Woodhouse , Lu Baolu , Joerg Roedel , Bjorn Helgaas , "Rafael J. Wysocki" , Len Brown , "open list:AMD IOMMU (AMD-VI)" , Linux Kernel Mailing List , Linux PCI , ACPI Devel Maling List , Raj Ashok , lalithambika.krishnakumar@intel.com, Mika Westerberg , Jean-Philippe Brucker , Prashant Malani , Benson Leung , Todd Broch , Alex Levin , Mattias Nissler , Rajat Jain , Bernie Keany , Aaron Durbin , Diego Rivas , Duncan Laurie , Furquan Shaikh , Jesse Barnes , Christian Kellner , Alex Williamson , Oliver O'Halloran , Saravana Kannan , Suzuki K Poulose , Arnd Bergmann Subject: Re: [PATCH v2 5/7] driver core: Add device location to "struct device" and expose it in sysfs Message-ID: <20200630153816.GD1785141@kroah.com> References: <20200630044943.3425049-1-rajatja@google.com> <20200630044943.3425049-6-rajatja@google.com> <20200630104948.GC856968@kuha.fi.intel.com> <20200630125216.GA1109228@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Tue, Jun 30, 2020 at 03:00:34PM +0200, Rafael J. Wysocki wrote: > On Tue, Jun 30, 2020 at 2:52 PM Greg Kroah-Hartman > wrote: > > > > On Tue, Jun 30, 2020 at 01:49:48PM +0300, Heikki Krogerus wrote: > > > On Mon, Jun 29, 2020 at 09:49:41PM -0700, Rajat Jain wrote: > > > > Add a new (optional) field to denote the physical location of a device > > > > in the system, and expose it in sysfs. This was discussed here: > > > > https://lore.kernel.org/linux-acpi/20200618184621.GA446639@kroah.com/ > > > > > > > > (The primary choice for attribute name i.e. "location" is already > > > > exposed as an ABI elsewhere, so settled for "site"). Individual buses > > > > that want to support this new attribute can opt-in by setting a flag in > > > > bus_type, and then populating the location of device while enumerating > > > > it. > > > > > > So why not just call it "physical_location"? > > > > That's better, and will allow us to put "3rd blue plug from the left, > > 4th row down" in there someday :) > > > > All of this is "relative" to the CPU, right? But what CPU? Again, how > > are the systems with drawers of PCI and CPUs and memory that can be > > added/removed at any point in time being handled here? What is > > "internal" and "external" for them? > > > > What exactly is the physical boundry here that is attempting to be > > described? > > Also, where is the "physical location" information going to come from? Who knows? :) Some BIOS seem to provide this, but do you trust that? > If that is the platform firmware (which I suspect is the anticipated > case), there may be problems with reliability related to that. s/may/will/ which means making the kernel inact a policy like this patch series tries to add, will result in a lot of broken systems, which is why I keep saying that it needs to be done in userspace. It's as if some of us haven't been down this road before and just keep being ignored... {sigh} greg k-h