From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [PATCH 1/2] kvm: Remove ability to assign a device without iommu support Date: Tue, 20 Dec 2011 10:03:16 +0100 Message-ID: <4EF04F54.9010500@siemens.com> References: <20111220030826.11829.9141.stgit@bling.home> <20111220031947.11829.66292.stgit@bling.home> <1324370959.22797.3.camel@lappy> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Alex Williamson , "avi@redhat.com" , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" To: Sasha Levin Return-path: Received: from goliath.siemens.de ([192.35.17.28]:17178 "EHLO goliath.siemens.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752501Ab1LTJDe (ORCPT ); Tue, 20 Dec 2011 04:03:34 -0500 In-Reply-To: <1324370959.22797.3.camel@lappy> Sender: kvm-owner@vger.kernel.org List-ID: On 2011-12-20 09:49, Sasha Levin wrote: > On Mon, 2011-12-19 at 20:19 -0700, Alex Williamson wrote: >> This option has no users and it exposes a security hole that we >> can allow devices to be assigned without iommu protection. Make >> KVM_DEV_ASSIGN_ENABLE_IOMMU a mandatory option. >> >> Signed-off-by: Alex Williamson >> --- >> >> virt/kvm/assigned-dev.c | 18 +++++++++--------- >> 1 files changed, 9 insertions(+), 9 deletions(-) >> >> diff --git a/virt/kvm/assigned-dev.c b/virt/kvm/assigned-dev.c >> index 3ad0925..a251a28 100644 >> --- a/virt/kvm/assigned-dev.c >> +++ b/virt/kvm/assigned-dev.c >> @@ -487,6 +487,9 @@ static int kvm_vm_ioctl_assign_device(struct kvm *kvm, >> struct kvm_assigned_dev_kernel *match; >> struct pci_dev *dev; >> >> + if (!(assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU)) >> + return -EINVAL; > > Could we just drop KVM_DEV_ASSIGN_ENABLE_IOMMU and do it by default? > calling KVM_ASSIGN_PCI_DEVICE without that flag set it pretty > meaningless. There is that thing called "backward compatibility". :) Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux