From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751438AbeEPXKX (ORCPT ); Wed, 16 May 2018 19:10:23 -0400 Received: from mga01.intel.com ([192.55.52.88]:4149 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751013AbeEPXKW (ORCPT ); Wed, 16 May 2018 19:10:22 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,408,1520924400"; d="scan'208";a="59269551" Date: Wed, 16 May 2018 17:12:21 -0600 From: Keith Busch To: Sinan Kaya Cc: Alexandru Gagniuc , bhelgaas@google.com, alex_gagniuc@dellteam.com, austin_bolen@dell.com, shyam_iyer@dell.com, Dongdong Liu , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] PCI: DPC: Clear AER status bits before disabling port containment Message-ID: <20180516231220.GA21659@localhost.localdomain> References: <20180516213306.27027-1-mr.nuke.me@gmail.com> <605540c0-b6c5-89a2-9d50-12a3005d9f88@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <605540c0-b6c5-89a2-9d50-12a3005d9f88@codeaurora.org> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 16, 2018 at 06:44:22PM -0400, Sinan Kaya wrote: > On 5/16/2018 5:33 PM, Alexandru Gagniuc wrote: > > AER status bits are sticky, and they survive system resets. Downstream > > devices are usually taken care of after re-enumerating the downstream > > busses, as the AER bits are cleared during probe(). > > > > However, nothing clears the bits of the port which contained the > > error. These sticky bits may leave some BIOSes to think that something > > bad happened, and print ominous messages on next boot. To prevent this, > > tidy up the AER status bits before releasing containment. > > > > Signed-off-by: Alexandru Gagniuc > > --- > > drivers/pci/pcie/dpc.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c > > index 8c57d607e603..bf82d6936556 100644 > > --- a/drivers/pci/pcie/dpc.c > > +++ b/drivers/pci/pcie/dpc.c > > @@ -112,6 +112,10 @@ static void dpc_work(struct work_struct *work) > > dpc->rp_pio_status = 0; > > } > > > > + /* DPC event made a mess of our AER status bits. Clean them up. */ > > + pci_cleanup_aer_error_status_regs(pdev); > > + /* TODO: Should we also use aer_print_error to log the event? */ > > + > > pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS, > > PCI_EXP_DPC_STATUS_TRIGGER | PCI_EXP_DPC_STATUS_INTERRUPT); > > > > > > I think Keith has a patch to fix this. It was under review at some point. Right, I do intend to following up on this, but I've had some trouble finding time the last few weeks. Sorry about that, things will clear up for me shortly.