From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga17.intel.com ([192.55.52.151]:32872 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933974AbeFLOlt (ORCPT ); Tue, 12 Jun 2018 10:41:49 -0400 Date: Tue, 12 Jun 2018 08:44:44 -0600 From: Keith Busch To: poza@codeaurora.org Cc: Sinan Kaya , Linux PCI , Bjorn Helgaas Subject: Re: [PATCH] PCI/AER: Prevent runtime power management during recovery Message-ID: <20180612144443.GA3142@localhost.localdomain> References: <20180611222918.1708-1-keith.busch@intel.com> <08e0ba9f-69cd-ea18-ae1b-d0795cceb306@codeaurora.org> <76f700a5484d82529272d94b4531e434@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <76f700a5484d82529272d94b4531e434@codeaurora.org> Sender: linux-pci-owner@vger.kernel.org List-ID: On Tue, Jun 12, 2018 at 01:21:53PM +0530, poza@codeaurora.org wrote: > On 2018-06-12 10:10, Sinan Kaya wrote: > > On 6/11/2018 6:29 PM, Keith Busch wrote: > > > A bridge that supports D3 but not hotplug will be subject to runtime > > > power management placing it in a non-operation power state if it > > > doesn't > > > have any devices attached. This patch will prevent this power > > > management > > > during error recovery so that the rescan at the end may be successful. > > > > If there is no card connected, why would the bridge observe a fatal > > error? > > fatal error could be coming from anywhere let us say below RootPort.. > and RP observes it and decides to take the tree down.... > Is that the case Keith is talking about ? Right, the err fatal handling removes all the devices below a bridge, making that bridge allowed for run time d3. > Why will re-enumeration be a problem even if runtime PM is active ? > I assume that enumeration will get bridge out of D3. That doesn't seem to be the case.