From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:35684 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726757AbgGGLRF (ORCPT ); Tue, 7 Jul 2020 07:17:05 -0400 Subject: Re: [PATCH v4 2/2] s390: virtio: PV needs VIRTIO I/O device protection References: <1594111477-15401-1-git-send-email-pmorel@linux.ibm.com> <1594111477-15401-3-git-send-email-pmorel@linux.ibm.com> <862dce70-1aed-ace0-cb7b-54844e812be3@de.ibm.com> From: Pierre Morel Message-ID: Date: Tue, 7 Jul 2020 13:16:53 +0200 MIME-Version: 1.0 In-Reply-To: <862dce70-1aed-ace0-cb7b-54844e812be3@de.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Christian Borntraeger , linux-kernel@vger.kernel.org Cc: pasic@linux.ibm.com, frankja@linux.ibm.com, mst@redhat.com, jasowang@redhat.com, cohuck@redhat.com, kvm@vger.kernel.org, linux-s390@vger.kernel.org, virtualization@lists.linux-foundation.org, thomas.lendacky@amd.com, david@gibson.dropbear.id.au, linuxram@us.ibm.com, heiko.carstens@de.ibm.com, gor@linux.ibm.com On 2020-07-07 13:12, Christian Borntraeger wrote: > > > On 07.07.20 10:44, Pierre Morel wrote: >> S390, protecting the guest memory against unauthorized host access >> needs to enforce VIRTIO I/O device protection through the use of >> VIRTIO_F_VERSION_1 and VIRTIO_F_IOMMU_PLATFORM. >> >> Signed-off-by: Pierre Morel >> --- >> arch/s390/kernel/uv.c | 25 +++++++++++++++++++++++++ >> 1 file changed, 25 insertions(+) >> >> diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c >> index c296e5c8dbf9..106330f6eda1 100644 >> --- a/arch/s390/kernel/uv.c >> +++ b/arch/s390/kernel/uv.c >> @@ -14,6 +14,7 @@ >> #include >> #include >> #include >> +#include >> #include >> #include >> #include >> @@ -413,3 +414,27 @@ static int __init uv_info_init(void) >> } >> device_initcall(uv_info_init); >> #endif >> + >> +/* >> + * arch_validate_virtio_iommu_platform >> + * @dev: the VIRTIO device being added >> + * >> + * Return value: returns -ENODEV if any features of the >> + * device breaks the protected virtualization >> + * 0 otherwise. >> + */ >> +int arch_validate_virtio_features(struct virtio_device *dev) >> +{ >> + if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) { >> + dev_warn(&dev->dev, "device must provide VIRTIO_F_VERSION_1\n"); > > I think you only want to warn if is_prot_virt_guest is true? We certainly > want to be able to run as a guest of older hypervisors with virtio 0.95, no? clear, yes. I will first check for PV as Connie sugested. > > >> + return is_prot_virt_guest() ? -ENODEV : 0; >> + } >> + >> + if (!virtio_has_feature(dev, VIRTIO_F_IOMMU_PLATFORM)) { >> + dev_warn(&dev->dev, >> + "device must provide VIRTIO_F_IOMMU_PLATFORM\n"); > > same here. Yes, Thanks, Pierre -- Pierre Morel IBM Lab Boeblingen