From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:39834 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751738AbdCMImd (ORCPT ); Mon, 13 Mar 2017 04:42:33 -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 32/63] drivers/pci/hotplug: Handle presence detection change properly Date: Mon, 13 Mar 2017 16:39:19 +0800 Message-Id: <20170313083416.664198066@linuxfoundation.org> In-Reply-To: <20170313083414.786638815@linuxfoundation.org> References: <20170313083414.786638815@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gavin Shan commit d7d55536c6cd1f80295b6d7483ad0587b148bde4 upstream. The surprise hotplug is driven by interrupt in PowerNV PCI hotplug driver. In the interrupt handler, pnv_php_interrupt(), we bail when pnv_pci_get_presence_state() returns zero wrongly. It causes the presence change event is always ignored incorrectly. This fixes the issue by bailing on error (non-zero value) returned from pnv_pci_get_presence_state(). 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 | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -713,8 +713,12 @@ static irqreturn_t pnv_php_interrupt(int added = !!(lsts & PCI_EXP_LNKSTA_DLLLA); } else if (sts & PCI_EXP_SLTSTA_PDC) { ret = pnv_pci_get_presence_state(php_slot->id, &presence); - if (!ret) + if (ret) { + dev_warn(&pdev->dev, "PCI slot [%s] error %d getting presence (0x%04x), to retry the operation.\n", + php_slot->name, ret, sts); return IRQ_HANDLED; + } + added = !!(presence == OPAL_PCI_SLOT_PRESENT); } else { return IRQ_NONE;