From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:48739 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757262AbcIMJAm (ORCPT ); Tue, 13 Sep 2016 05:00:42 -0400 Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u8D8wcwt123268 for ; Tue, 13 Sep 2016 05:00:42 -0400 Received: from e19.ny.us.ibm.com (e19.ny.us.ibm.com [129.33.205.209]) by mx0a-001b2d01.pphosted.com with ESMTP id 25e0b1qerr-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 13 Sep 2016 05:00:41 -0400 Received: from localhost by e19.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 13 Sep 2016 05:00:40 -0400 From: Yongji Xie To: bhelgaas@google.com Cc: linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, alex.williamson@redhat.com, paulus@samba.org, aik@ozlabs.ru, gwshan@linux.vnet.ibm.com, benh@kernel.crashing.org, mpe@ellerman.id.au, zhong@linux.vnet.ibm.com Subject: [PATCH v5 2/4] PCI: Ignore enforced alignment to VF BARs Date: Tue, 13 Sep 2016 17:00:32 +0800 In-Reply-To: <1473757234-5284-1-git-send-email-xyjxie@linux.vnet.ibm.com> References: <1473757234-5284-1-git-send-email-xyjxie@linux.vnet.ibm.com> Message-Id: <1473757234-5284-3-git-send-email-xyjxie@linux.vnet.ibm.com> Sender: linux-pci-owner@vger.kernel.org List-ID: VF BARs are read-only zeroes according to SRIOV spec, the normal way(writing BARs) of allocating resources wouldn't be applied to VFs. The VFs' resources would be allocated when we enable SR-IOV capability. So we should not try to reassign alignment after we enable VFs. It's meaningless and will release the allocated resources which leads to a bug. Signed-off-by: Yongji Xie --- drivers/pci/pci.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 2d85a96..b8357d7 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5048,6 +5048,15 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev) resource_size_t align, size; u16 command; + /* + * VF BARs are RO zero according to SR-IOV spec 3.4.1.11. Their + * resources would be allocated when we enable them and not be + * re-allocated any more. So we should never try to reassign + * VF's alignment here. + */ + if (dev->is_virtfn) + return; + /* check if specified PCI is target device to reassign */ align = pci_specified_resource_alignment(dev); if (!align) -- 1.7.9.5