From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753702AbcFEVn6 (ORCPT ); Sun, 5 Jun 2016 17:43:58 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:43009 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753557AbcFEVm6 (ORCPT ); Sun, 5 Jun 2016 17:42:58 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Gavin Shan , "Guilherme G. Piccoli" , Michael Ellerman Subject: [PATCH 4.4 67/99] Revert "powerpc/eeh: Fix crash in eeh_add_device_early() on Cell" Date: Sun, 5 Jun 2016 14:41:40 -0700 Message-Id: <20160605213909.558132864@linuxfoundation.org> X-Mailer: git-send-email 2.8.3 In-Reply-To: <20160605213902.974592018@linuxfoundation.org> References: <20160605213902.974592018@linuxfoundation.org> User-Agent: quilt/0.64 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 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Guilherme G. Piccoli commit c2078d9ef600bdbe568c89e5ddc2c6f15b7982c8 upstream. This reverts commit 89a51df5ab1d38b257300b8ac940bbac3bb0eb9b. The function eeh_add_device_early() is used to perform EEH initialization in devices added later on the system, like in hotplug/DLPAR scenarios. Since the commit 89a51df5ab1d ("powerpc/eeh: Fix crash in eeh_add_device_early() on Cell") a new check was introduced in this function - Cell has no EEH capabilities which led to kernel oops if hotplug was performed, so checking for eeh_enabled() was introduced to avoid the issue. However, in architectures that EEH is present like pSeries or PowerNV, we might reach a case in which no PCI devices are present on boot time and so EEH is not initialized. Then, if a device is added via DLPAR for example, eeh_add_device_early() fails because eeh_enabled() is false, and EEH end up not being enabled at all. This reverts the aforementioned patch since a new verification was introduced by the commit d91dafc02f42 ("powerpc/eeh: Delay probing EEH device during hotplug") and so the original Cell issue does not happen anymore. Reviewed-by: Gavin Shan Signed-off-by: Guilherme G. Piccoli Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/eeh.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -1072,7 +1072,7 @@ void eeh_add_device_early(struct pci_dn struct pci_controller *phb; struct eeh_dev *edev = pdn_to_eeh_dev(pdn); - if (!edev || !eeh_enabled()) + if (!edev) return; if (!eeh_has_flag(EEH_PROBE_MODE_DEVTREE))