From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-da0-f51.google.com (mail-da0-f51.google.com [209.85.210.51]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 64CE72C0097 for ; Fri, 23 Nov 2012 13:50:11 +1100 (EST) Received: by mail-da0-f51.google.com with SMTP id i30so1941950dad.38 for ; Thu, 22 Nov 2012 18:50:09 -0800 (PST) Message-ID: <50AEE45C.80603@ozlabs.ru> Date: Fri, 23 Nov 2012 13:50:04 +1100 From: Alexey Kardashevskiy MIME-Version: 1.0 To: Benjamin Herrenschmidt Subject: [PATCH] powerpc/pseries: Fix kernel crash caused by NULL PE Content-Type: multipart/mixed; boundary="------------010108090804080207040608" Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, David Gibson List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , This is a multi-part message in MIME format. --------------010108090804080207040608 Content-Type: text/plain; charset=KOI8-R; format=flowed Content-Transfer-Encoding: 7bit While hooking MSI interrupts, the corresponding device tree node of the PE that the PCI device has been put into should be checked. However, those PCI devices (e.g. VirtIO based PCI devices) that don't have EEH capability shouldn't have the associated PE. So we shouldn't try to get the PE's device tree node. Otherwise, it would cause kernel crash. Actually, it was introduced by commit 66523d9f ("powerpc/eeh: Trace error based on PE from beginning"). Signed-off-by: Alexey Kardashevskiy Signed-off-by: Gavin Shan --- arch/powerpc/platforms/pseries/msi.c | 11 +++++++++-- 1 files changed, 9 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/platforms/pseries/msi.c b/arch/powerpc/platforms/pseries/msi.c index d19f497..9284e42 100644 --- a/arch/powerpc/platforms/pseries/msi.c +++ b/arch/powerpc/platforms/pseries/msi.c @@ -218,9 +218,16 @@ static struct device_node *find_pe_dn(struct pci_dev *dev, int *total) if (!dn) return NULL; - /* Get the top level device in the PE */ + /* + * Get the top level device in the PE, but some PCI devices + * without EEH capability (e.g. VirtIO based PCI devices) + * don't have the associated PE. So we should not get the + * top level device from PE for those PCI devices. + */ edev = of_node_to_eeh_dev(dn); - edev = list_first_entry(&edev->pe->edevs, struct eeh_dev, list); + if (edev->pe) + edev = list_first_entry(&edev->pe->edevs, + struct eeh_dev, list); dn = eeh_dev_to_of_node(edev); if (!dn) return NULL; -- 1.7.5.4 --------------010108090804080207040608 Content-Type: text/plain; charset=UTF-8; name="Attached Message Part" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="Attached Message Part" --------------010108090804080207040608--