| Message ID | 1523588509-4868-1-git-send-email-jasowang@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, 13 Apr 2018 11:01:49 +0800 Jason Wang <jasowang@redhat.com> wrote: > When IOMMU is enabled, we store virtqueue metadata as iova (though it > may has _phys suffix) and access them through dma helpers. Any > translation failures could be reported by IOMMU. > > In this case, trying to validate iova against gpa won't work and will > cause a false error reporting. So this patch bypasses the ring > verification if IOMMU is enabled which is similar to the behavior > before 0ca1fd2d6878 that calls vhost_memory_map() which is a nop when > IOMMU is enabled. > > Fixes: 0ca1fd2d6878 ("vhost: Simplify ring verification checks") > Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> > Cc: Igor Mammedov <imammedo@redhat.com> > Cc: Michael S. Tsirkin <mst@redhat.com> > Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Igor Mammedov <imammedo@redhat.com> Looks like candidat for 2.12 if it's not too late? > --- > hw/virtio/vhost.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c > index f51bf57..9d5850a 100644 > --- a/hw/virtio/vhost.c > +++ b/hw/virtio/vhost.c > @@ -342,6 +342,10 @@ static int vhost_verify_ring_mappings(struct vhost_dev *dev, > "used ring" > }; > > + if (vhost_dev_has_iommu(dev)) { > + return 0; > + } > + > for (i = 0; i < dev->nvqs; ++i) { > struct vhost_virtqueue *vq = dev->vqs + i; >
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index f51bf57..9d5850a 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -342,6 +342,10 @@ static int vhost_verify_ring_mappings(struct vhost_dev *dev, "used ring" }; + if (vhost_dev_has_iommu(dev)) { + return 0; + } + for (i = 0; i < dev->nvqs; ++i) { struct vhost_virtqueue *vq = dev->vqs + i;
When IOMMU is enabled, we store virtqueue metadata as iova (though it may has _phys suffix) and access them through dma helpers. Any translation failures could be reported by IOMMU. In this case, trying to validate iova against gpa won't work and will cause a false error reporting. So this patch bypasses the ring verification if IOMMU is enabled which is similar to the behavior before 0ca1fd2d6878 that calls vhost_memory_map() which is a nop when IOMMU is enabled. Fixes: 0ca1fd2d6878 ("vhost: Simplify ring verification checks") Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> --- hw/virtio/vhost.c | 4 ++++ 1 file changed, 4 insertions(+)