From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3yj4nf1kZwzDrJB for ; Thu, 23 Nov 2017 14:39:33 +1100 (AEDT) Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vAN3cvcf011013 for ; Wed, 22 Nov 2017 22:39:31 -0500 Received: from e06smtp11.uk.ibm.com (e06smtp11.uk.ibm.com [195.75.94.107]) by mx0b-001b2d01.pphosted.com with ESMTP id 2edp0xt53d-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 22 Nov 2017 22:39:30 -0500 Received: from localhost by e06smtp11.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 23 Nov 2017 03:39:29 -0000 From: Vaibhav Jain To: linuxppc-dev@lists.ozlabs.org, Frederic Barrat Cc: Vaibhav Jain , Andrew Donnellan , Christophe Lombard , Philippe Bergheaud , "Alastair D'Silva" , Michael Ellerman , stable@vger.kernel.org Subject: [PATCH v3] cxl: Check if vphb exists before iterating over AFU devices Date: Thu, 23 Nov 2017 09:08:57 +0530 Message-Id: <20171123033857.13122-1-vaibhav@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , During an eeh a kernel-oops is reported if no vPHB is allocated to the AFU. This happens as during AFU init, an error in creation of vPHB is a non-fatal error. Hence afu->phb should always be checked for NULL before iterating over it for the virtual AFU pci devices. This patch fixes the kenel-oops by adding a NULL pointer check for afu->phb before it is dereferenced. Fixes: 9e8df8a2196("cxl: EEH support") Cc: stable@vger.kernel.org Signed-off-by: Vaibhav Jain --- Changelog: v3 -> Fixed a reverse NULL check [Fred] Resend -> Added the 'Fixes' info and marking the patch to stable tree [Mpe] v2 -> Added the vphb NULL check to cxl_vphb_error_detected() [Andrew] --- drivers/misc/cxl/pci.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c index bb7fd3f4edab..19969ee86d6f 100644 --- a/drivers/misc/cxl/pci.c +++ b/drivers/misc/cxl/pci.c @@ -2083,6 +2083,9 @@ static pci_ers_result_t cxl_vphb_error_detected(struct cxl_afu *afu, /* There should only be one entry, but go through the list * anyway */ + if (afu->phb == NULL) + return result; + list_for_each_entry(afu_dev, &afu->phb->bus->devices, bus_list) { if (!afu_dev->driver) continue; @@ -2124,8 +2127,7 @@ static pci_ers_result_t cxl_pci_error_detected(struct pci_dev *pdev, * Tell the AFU drivers; but we don't care what they * say, we're going away. */ - if (afu->phb != NULL) - cxl_vphb_error_detected(afu, state); + cxl_vphb_error_detected(afu, state); } return PCI_ERS_RESULT_DISCONNECT; } @@ -2265,6 +2267,9 @@ static pci_ers_result_t cxl_pci_slot_reset(struct pci_dev *pdev) if (cxl_afu_select_best_mode(afu)) goto err; + if (afu->phb == NULL) + continue; + list_for_each_entry(afu_dev, &afu->phb->bus->devices, bus_list) { /* Reset the device context. * TODO: make this less disruptive @@ -2327,6 +2332,9 @@ static void cxl_pci_resume(struct pci_dev *pdev) for (i = 0; i < adapter->slices; i++) { afu = adapter->afu[i]; + if (afu->phb == NULL) + continue; + list_for_each_entry(afu_dev, &afu->phb->bus->devices, bus_list) { if (afu_dev->driver && afu_dev->driver->err_handler && afu_dev->driver->err_handler->resume) -- 2.14.3