From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:34280 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725894AbgFQLWj (ORCPT ); Wed, 17 Jun 2020 07:22:39 -0400 Date: Wed, 17 Jun 2020 13:22:22 +0200 From: Heiko Carstens Subject: Re: [PATCH v3 1/1] s390: virtio: let arch accept devices without IOMMU feature Message-ID: <20200617112222.GF4479@osiris> References: <1592390637-17441-1-git-send-email-pmorel@linux.ibm.com> <1592390637-17441-2-git-send-email-pmorel@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1592390637-17441-2-git-send-email-pmorel@linux.ibm.com> Sender: linux-s390-owner@vger.kernel.org List-ID: To: Pierre Morel Cc: linux-kernel@vger.kernel.org, pasic@linux.ibm.com, borntraeger@de.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, gor@linux.ibm.com On Wed, Jun 17, 2020 at 12:43:57PM +0200, Pierre Morel wrote: > An architecture protecting the guest memory against unauthorized host > access may want to enforce VIRTIO I/O device protection through the > use of VIRTIO_F_IOMMU_PLATFORM. > > Let's give a chance to the architecture to accept or not devices > without VIRTIO_F_IOMMU_PLATFORM. > > Signed-off-by: Pierre Morel > Acked-by: Jason Wang > Acked-by: Christian Borntraeger > --- > arch/s390/mm/init.c | 6 ++++++ > drivers/virtio/virtio.c | 22 ++++++++++++++++++++++ > include/linux/virtio.h | 2 ++ > 3 files changed, 30 insertions(+) > > diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c > index 6dc7c3b60ef6..215070c03226 100644 > --- a/arch/s390/mm/init.c > +++ b/arch/s390/mm/init.c > @@ -45,6 +45,7 @@ > #include > #include > #include > +#include > > pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir); > > @@ -161,6 +162,11 @@ bool force_dma_unencrypted(struct device *dev) > return is_prot_virt_guest(); > } > > +int arch_needs_virtio_iommu_platform(struct virtio_device *dev) > +{ > + return is_prot_virt_guest(); > +} > + > /* protected virtualization */ > static void pv_init(void) Can we please stop dumping random code to arch/s390/mm/init.c? All the protected virtualization functions should go into a separate file (e.g. mem_encrypt.c like on x86), some of which could also be in header files. Please consider this a comment for the future.. just go ahead with this patch as-is.