linux-kernel - [RFC PATCH] vdpa: mandate 1.0 device

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Thu,  8 Apr 2021 16:26:48 +0800
From:   Jason Wang <jasowang@...hat.com>
To:     mst@...hat.com, jasowang@...hat.com,
        virtualization@...ts.linux-foundation.org,
        linux-kernel@...r.kernel.org
Cc:     parav@...dia.com, elic@...dia.com
Subject: [RFC PATCH] vdpa: mandate 1.0 device

This patch mandates 1.0 for vDPA devices. The goal is to have the
semantic of normative statement in the virtio spec and eliminate the
burden of transitional device for both vDPA bus and vDPA parent.

uAPI seems fine since all the vDPA parent mandates
VIRTIO_F_ACCESS_PLATFORM which implies 1.0 devices.

For legacy guests, it can still work since Qemu will mediate when
necessary (e.g doing the endian conversion).

Signed-off-by: Jason Wang <jasowang@...hat.com>
---
 include/linux/vdpa.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 0fefeb976877..cfde4ec999b4 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -6,6 +6,7 @@
 #include <linux/device.h>
 #include <linux/interrupt.h>
 #include <linux/vhost_iotlb.h>
+#include <uapi/linux/virtio_config.h>
 
 /**
  * vDPA callback definition.
@@ -317,6 +318,11 @@ static inline int vdpa_set_features(struct vdpa_device *vdev, u64 features)
 {
         const struct vdpa_config_ops *ops = vdev->config;
 
+        /* Mandating 1.0 to have semantics of normative statements in
+         * the spec. */
+        if (!(features & BIT_ULL(VIRTIO_F_VERSION_1)))
+		return -EINVAL;
+
 	vdev->features_valid = true;
         return ops->set_features(vdev, features);
 }
-- 
2.25.1