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=-11.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 047E7C4741F for ; Fri, 25 Sep 2020 21:59:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B5765206FC for ; Fri, 25 Sep 2020 21:59:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601071140; bh=cuxPA7oSZFL1vZUF+tnIoB0ZayYgP50U6fmiU2EcMzA=; h=Date:From:To:Cc:Subject:In-Reply-To:List-ID:From; b=pXXbf4cXcSRf5DM1hXsvskVoleckY90iSt7/siWjvvbetL8Fu/qn42fz+nMITuCqB 4F8wTk9nfK3CQfE5Zmcq2hkSzJH/I2Qvmr2AQ/ZRJCE4CGQA4FZ3m4L0Kk9DBYlbzg Ta3w6E3DkuSPNyKQRgXdr1XE6g73kQefcCMW2Yvs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727599AbgIYV66 (ORCPT ); Fri, 25 Sep 2020 17:58:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:45542 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726412AbgIYV66 (ORCPT ); Fri, 25 Sep 2020 17:58:58 -0400 Received: from localhost (52.sub-72-107-123.myvzw.com [72.107.123.52]) (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 03CF72068D; Fri, 25 Sep 2020 21:58:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601071137; bh=cuxPA7oSZFL1vZUF+tnIoB0ZayYgP50U6fmiU2EcMzA=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=pYu+Q8d0tshd0wLJaLE3NsSqe5M7UGbip4En6laQrjy/GMkBFfAz20Q/fkW8mPtsg hLmTttLBKQB8TuCTZlELGk5bonqgMhSnGR3RM8Ci3WRe0gVBJV1VwxavPqUIszKWc1 8BVzfoF1M9df78sEdoDFciVVGJsIzxUINd515M38= Date: Fri, 25 Sep 2020 16:58:54 -0500 From: Bjorn Helgaas To: Sean V Kelley Cc: bhelgaas@google.com, Jonathan.Cameron@huawei.com, rafael.j.wysocki@intel.com, ashok.raj@intel.com, tony.luck@intel.com, sathyanarayanan.kuppuswamy@intel.com, qiuxu.zhuo@intel.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 05/10] PCI/AER: Apply function level reset to RCiEP on fatal error Message-ID: <20200925215854.GA2460270@bjorn-Precision-5520> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200922213859.108826-6-seanvk.dev@oregontracks.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 22, 2020 at 02:38:54PM -0700, Sean V Kelley wrote: > From: Qiuxu Zhuo > > Attempt to do function level reset for an RCiEP associated with an > RCEC device on fatal error. > > Signed-off-by: Qiuxu Zhuo > --- > drivers/pci/pcie/err.c | 31 ++++++++++++++++++++++--------- > 1 file changed, 22 insertions(+), 9 deletions(-) > > diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c > index e575fa6cee63..5380ecc41506 100644 > --- a/drivers/pci/pcie/err.c > +++ b/drivers/pci/pcie/err.c > @@ -169,6 +169,17 @@ static void pci_bridge_walk(struct pci_dev *bridge, int (*cb)(struct pci_dev *, > cb(bridge, userdata); > } > > +static pci_ers_result_t flr_on_rciep(struct pci_dev *dev) > +{ > + if (!pcie_has_flr(dev)) > + return PCI_ERS_RESULT_NONE; > + > + if (pcie_flr(dev)) > + return PCI_ERS_RESULT_DISCONNECT; > + > + return PCI_ERS_RESULT_RECOVERED; > +} Either we reset the device or we didn't; there is no third option. If I read it correctly, nothing in pcie_do_recovery() cares about the difference between PCI_ERS_RESULT_NONE and PCI_ERS_RESULT_DISCONNECT. The status does get returned, but only edr_handle_event() looks at it, and it doesn't care about the difference either. So I think this should just return PCI_ERS_RESULT_RECOVERED or PCI_ERS_RESULT_DISCONNECT. > pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, > pci_channel_state_t state, > pci_ers_result_t (*reset_subordinate_devices)(struct pci_dev *pdev)) > @@ -195,15 +206,17 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, > if (state == pci_channel_io_frozen) { > pci_bridge_walk(bridge, report_frozen_detected, &status); > if (type == PCI_EXP_TYPE_RC_END) { > - pci_warn(dev, "link reset not possible for RCiEP\n"); > - status = PCI_ERS_RESULT_NONE; > - goto failed; > - } > - > - status = reset_subordinate_devices(bridge); > - if (status != PCI_ERS_RESULT_RECOVERED) { > - pci_warn(dev, "subordinate device reset failed\n"); > - goto failed; > + status = flr_on_rciep(dev); > + if (status != PCI_ERS_RESULT_RECOVERED) { > + pci_warn(dev, "function level reset failed\n"); > + goto failed; > + } > + } else { > + status = reset_subordinate_devices(bridge); > + if (status != PCI_ERS_RESULT_RECOVERED) { > + pci_warn(dev, "subordinate device reset failed\n"); > + goto failed; > + } > } > } else { > pci_bridge_walk(bridge, report_normal_detected, &status); > -- > 2.28.0 >