Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752226AbdHQIPN (ORCPT ); Thu, 17 Aug 2017 04:15:13 -0400 Received: from mail-wr0-f194.google.com ([209.85.128.194]:33201 "EHLO mail-wr0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751646AbdHQIPH (ORCPT ); Thu, 17 Aug 2017 04:15:07 -0400 From: Jan Glauber To: Bjorn Helgaas , linux-pci@vger.kernel.org, Alex Williamson Cc: linux-kernel@vger.kernel.org, david.daney@cavium.com, Jon Masters , Robert Richter , linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, Jan Glauber Subject: [PATCH v2 3/3] vfio/pci: Don't probe devices that can't be reset Date: Thu, 17 Aug 2017 10:14:23 +0200 Message-Id: <1502957663-5527-4-git-send-email-jglauber@cavium.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1502957663-5527-1-git-send-email-jglauber@cavium.com> References: <1502957663-5527-1-git-send-email-jglauber@cavium.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1011 Lines: 32 If a PCI device supports neither function-level reset, nor slot or bus reset then refuse to probe it. A line is printed to inform the user. Without this change starting qemu with a vfio-pci device can lead to a kernel panic on some Cavium cn8xxx systems, depending on the used device. Signed-off-by: Jan Glauber --- drivers/vfio/pci/vfio_pci.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 063c1ce..029ba13 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -1196,6 +1196,12 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) if (pdev->hdr_type != PCI_HEADER_TYPE_NORMAL) return -EINVAL; + ret = pci_probe_reset_bus(pdev->bus); + if (ret) { + dev_warn(&pdev->dev, "Refusing to probe because reset is not possible.\n"); + return ret; + } + group = vfio_iommu_group_get(&pdev->dev); if (!group) return -EINVAL; -- 2.9.0.rc0.21.g7777322