From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp07.au.ibm.com (e23smtp07.au.ibm.com [202.81.31.140]) (using TLSv1.2 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3qzVSx0mj0zDqG1 for ; Tue, 3 May 2016 15:43:13 +1000 (AEST) Received: from localhost by e23smtp07.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 3 May 2016 15:43:12 +1000 Received: from d23relay08.au.ibm.com (d23relay08.au.ibm.com [9.185.71.33]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id DA0C73578067 for ; Tue, 3 May 2016 15:43:09 +1000 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay08.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u435h1wR59441336 for ; Tue, 3 May 2016 15:43:09 +1000 Received: from d23av02.au.ibm.com (localhost [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u435gbiw007515 for ; Tue, 3 May 2016 15:42:37 +1000 From: Gavin Shan To: linuxppc-dev@lists.ozlabs.org Cc: benh@kernel.crashing.org, mpe@ellerman.id.au, aik@ozlabs.ru, alistair@popple.id.au, Gavin Shan Subject: [PATCH v9 24/26] powerpc/pci: Don't scan empty slot Date: Tue, 3 May 2016 15:41:43 +1000 Message-Id: <1462254105-24128-25-git-send-email-gwshan@linux.vnet.ibm.com> In-Reply-To: <1462254105-24128-1-git-send-email-gwshan@linux.vnet.ibm.com> References: <1462254105-24128-1-git-send-email-gwshan@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , In hotplug case, function pci_add_pci_devices() is called to rescan the specified PCI bus, which might not have any child devices. Access to the PCI bus's child device node will cause kernel crash without exception. This adds one more check to skip scanning PCI bus that doesn't have any subordinate devices from device-tree, in order to avoid kernel crash. Signed-off-by: Gavin Shan Reviewed-by: Alexey Kardashevskiy --- arch/powerpc/kernel/pci-hotplug.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/pci-hotplug.c b/arch/powerpc/kernel/pci-hotplug.c index 46587a1..2d71269 100644 --- a/arch/powerpc/kernel/pci-hotplug.c +++ b/arch/powerpc/kernel/pci-hotplug.c @@ -120,7 +120,8 @@ void pci_hp_add_devices(struct pci_bus *bus) if (mode == PCI_PROBE_DEVTREE) { /* use ofdt-based probe */ of_rescan_bus(dn, bus); - } else if (mode == PCI_PROBE_NORMAL) { + } else if (mode == PCI_PROBE_NORMAL && + dn->child && PCI_DN(dn->child)) { /* * Use legacy probe. In the partial hotplug case, we * probably have grandchildren devices unplugged. So -- 2.1.0