From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754330Ab3AJXda (ORCPT ); Thu, 10 Jan 2013 18:33:30 -0500 Received: from hydra.sisk.pl ([212.160.235.94]:37224 "EHLO hydra.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751742Ab3AJXd2 (ORCPT ); Thu, 10 Jan 2013 18:33:28 -0500 From: "Rafael J. Wysocki" To: Yinghai Lu Cc: Myron Stowe , Jiang Liu , Jiang Liu , Yijing Wang , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Myron Stowe , bhelgaas Subject: Re: [PATCH v3 3/6] ACPI/pci_slot: update PCI slot information when PCI hotplug event happens Date: Fri, 11 Jan 2013 00:39:12 +0100 Message-ID: <1410202.K95a8u1BYT@vostro.rjw.lan> User-Agent: KMail/4.9.5 (Linux/3.8.0-rc3+; KDE/4.9.5; x86_64; ; ) In-Reply-To: References: <1357663945-16054-1-git-send-email-jiang.liu@huawei.com> <2704169.6ID6mDVPAt@vostro.rjw.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday, January 10, 2013 03:03:53 PM Yinghai Lu wrote: > On Thu, Jan 10, 2013 at 1:50 PM, Rafael J. Wysocki wrote: > > Well, I don't see what functional problems that can bring. > > > > In theory people may want to have them as modules to avoid loading them on > > systems that don't use PCI hotplug, but honestly I think that the complexity > > this causes us to deal with is not worth it. > > > > Moreover, removing the modularity may actually allow us to solve some ordering > > issues once and for good. > > No, the world is not really ideal yet. > > looks like laptops have problem with pci express cards. > > when pciehp is used, surprise insert/removal does not work because > PresDect does not change properly, so no interrupt is generated. > --- i suspects that is silicon problem. > > but when acpiphp is used, that surprise insert/removal is working. > > some laptop like thinkpad, just don't give osc to kernel.. > [ 0.505117] pci0000:00: Requesting ACPI _OSC control (0x1d) > [ 0.505413] pci0000:00: ACPI _OSC request failed (AE_SUPPORT), > returned control mask: 0x0d > [ 0.505517] ACPI _OSC control for PCIe not granted, disabling ASPM > > and other laptop give that to kernel, in recent kernel will not give > acpiphp to have that slot, because it want to hold that for pciehp. > poor user have to pass 'pci_aspm=off" to disable _OSC for all. > --- please check the mail that i forward to you yesterday. Yes, this is a bug, but I'm not sure how to fix it yet. > Anyway, we do need to let the user to have choice to use acpiphp and pciehp. > and it should be first come and first serve policy. And that's why you think they should be modules? I disagree if so. Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.