From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752593AbdCMJNS (ORCPT ); Mon, 13 Mar 2017 05:13:18 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:39890 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751639AbdCMImf (ORCPT ); Mon, 13 Mar 2017 04:42:35 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hank Chang , Gavin Shan , Willie Liauw , Michael Ellerman Subject: [PATCH 4.9 33/63] drivers/pci/hotplug: Fix initial state for empty slot Date: Mon, 13 Mar 2017 16:39:20 +0800 Message-Id: <20170313083416.715345958@linuxfoundation.org> X-Mailer: git-send-email 2.12.0 In-Reply-To: <20170313083414.786638815@linuxfoundation.org> References: <20170313083414.786638815@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gavin Shan commit d0c424971f70501ec0a0364117b9934db039c9cc upstream. In PowerNV PCI hotplug driver, the initial PCI slot's state is set to PNV_PHP_STATE_POPULATED if no PCI devices are connected to the slot. The PCI devices that are hot added to the slot won't be probed and populated because of the check in pnv_php_enable(): /* Check if the slot has been configured */ if (php_slot->state != PNV_PHP_STATE_REGISTERED) return 0; This fixes the issue by leaving the slot in PNV_PHP_STATE_REGISTERED state initially if nothing is connected to the slot. Fixes: 360aebd85a4 ("drivers/pci/hotplug: Support surprise hotplug in powernv driver") Reported-by: Hank Chang Signed-off-by: Gavin Shan Tested-by: Willie Liauw Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- drivers/pci/hotplug/pnv_php.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -436,9 +436,21 @@ static int pnv_php_enable(struct pnv_php if (ret) return ret; - /* Proceed if there have nothing behind the slot */ - if (presence == OPAL_PCI_SLOT_EMPTY) + /* + * Proceed if there have nothing behind the slot. However, + * we should leave the slot in registered state at the + * beginning. Otherwise, the PCI devices inserted afterwards + * won't be probed and populated. + */ + if (presence == OPAL_PCI_SLOT_EMPTY) { + if (!php_slot->power_state_check) { + php_slot->power_state_check = true; + + return 0; + } + goto scan; + } /* * If the power supply to the slot is off, we can't detect