[PATCH v2 0/3] Virtio dmabuf improvements

[PATCH v2 0/3] Virtio dmabuf improvements

[Albert Esteve]

v1: https://www.mail-archive.com/qemu-devel@nongnu.org/msg1005257.html
v1 -> v2:
  - Solved an unitialized uuid value on vhost-user source
  - Changed cleanup strategy, and traverse all objects in the
    table to remove them instead.

Various improvements for the virtio-dmabuf module.
This patch includes:

- Check for ownership before allowing a vhost device
  to remove an object from the table.
- Properly cleanup shared resources if a vhost device
  object gets cleaned up.
- Rename virtio dmabuf functions to `virtio_dmabuf_*`

Albert Esteve (3):
  hw/virtio: check owner for removing objects
  hw/virtio: cleanup shared resources
  hw/virtio: rename virtio dmabuf API

 hw/display/virtio-dmabuf.c        | 36 ++++++++++++---
 hw/virtio/vhost-user.c            | 31 ++++++++++---
 hw/virtio/vhost.c                 |  3 ++
 include/hw/virtio/virtio-dmabuf.h | 43 ++++++++++-------
 tests/unit/test-virtio-dmabuf.c   | 77 ++++++++++++++++++++++---------
 5 files changed, 138 insertions(+), 52 deletions(-)

-- 
2.43.0

[PATCH v2 1/3] hw/virtio: check owner for removing objects

[Albert Esteve]

Shared objects lack spoofing protection.
For VHOST_USER_BACKEND_SHARED_OBJECT_REMOVE messages
received by the vhost-user interface, any backend was
allowed to remove entries from the shared table just
by knowing the UUID. Only the owner of the entry
shall be allowed to removed their resources
from the table.

To fix that, add a check for all
*SHARED_OBJECT_REMOVE messages received.
A vhost device can only remove TYPE_VHOST_DEV
entries that are owned by them, otherwise skip
the removal, and inform the device that the entry
has not been removed in the answer.

Signed-off-by: Albert Esteve <aesteve@redhat.com>
---
 hw/virtio/vhost-user.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index f214df804b..1c3f2357be 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -1611,11 +1611,27 @@ vhost_user_backend_handle_shared_object_add(struct vhost_dev *dev,
 }
 
 static int
-vhost_user_backend_handle_shared_object_remove(VhostUserShared *object)
+vhost_user_backend_handle_shared_object_remove(struct vhost_dev *dev,
+                                               VhostUserShared *object)
 {
     QemuUUID uuid;
 
     memcpy(uuid.data, object->uuid, sizeof(object->uuid));
+    switch (virtio_object_type(&uuid)) {
+    case TYPE_VHOST_DEV:
+    {
+        struct vhost_dev *owner = virtio_lookup_vhost_device(&uuid);
+        if (owner == NULL || dev != owner) {
+            /* Not allowed to remove non-owned entries */
+            return 0;
+        }
+        break;
+    }
+    default:
+        /* Not allowed to remove non-owned entries */
+        return 0;
+    }
+
     return virtio_remove_resource(&uuid);
 }
 
@@ -1794,7 +1810,8 @@ static gboolean backend_read(QIOChannel *ioc, GIOCondition condition,
         ret = vhost_user_backend_handle_shared_object_add(dev, &payload.object);
         break;
     case VHOST_USER_BACKEND_SHARED_OBJECT_REMOVE:
-        ret = vhost_user_backend_handle_shared_object_remove(&payload.object);
+        ret = vhost_user_backend_handle_shared_object_remove(dev,
+                                                             &payload.object);
         break;
     case VHOST_USER_BACKEND_SHARED_OBJECT_LOOKUP:
         ret = vhost_user_backend_handle_shared_object_lookup(dev->opaque, ioc,
-- 
2.43.0

[PATCH v2 2/3] hw/virtio: cleanup shared resources

[Albert Esteve]

Ensure that we cleanup all virtio shared
resources when the vhost devices is cleaned
up (after a hot unplug, or a crash).

To do so, we add a new function to the virtio_dmabuf
API called `virtio_dmabuf_vhost_cleanup`, which
loop through the table and removes all
resources owned by the vhost device parameter.

Also, add a test to verify that the new
function in the API behaves as expected.

Signed-off-by: Albert Esteve <aesteve@redhat.com>
---
 hw/display/virtio-dmabuf.c        | 22 +++++++++++++++++++++
 hw/virtio/vhost.c                 |  3 +++
 include/hw/virtio/virtio-dmabuf.h | 10 ++++++++++
 tests/unit/test-virtio-dmabuf.c   | 33 +++++++++++++++++++++++++++++++
 4 files changed, 68 insertions(+)

diff --git a/hw/display/virtio-dmabuf.c b/hw/display/virtio-dmabuf.c
index 3dba4577ca..6688809777 100644
--- a/hw/display/virtio-dmabuf.c
+++ b/hw/display/virtio-dmabuf.c
@@ -136,6 +136,28 @@ SharedObjectType virtio_object_type(const QemuUUID *uuid)
     return vso->type;
 }
 
+static bool virtio_dmabuf_resource_is_owned(gpointer key,
+                                            gpointer value,
+                                            gpointer dev)
+{
+    VirtioSharedObject *vso;
+
+    vso = (VirtioSharedObject *) value;
+    return vso->type == TYPE_VHOST_DEV && vso->value == dev;
+}
+
+int virtio_dmabuf_vhost_cleanup(struct vhost_dev *dev)
+{
+    int num_removed;
+
+    g_mutex_lock(&lock);
+    num_removed = g_hash_table_foreach_remove(
+        resource_uuids, (GHRFunc) virtio_dmabuf_resource_is_owned, dev);
+    g_mutex_unlock(&lock);
+
+    return num_removed;
+}
+
 void virtio_free_resources(void)
 {
     g_mutex_lock(&lock);
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 2c9ac79468..c5622eac14 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -16,6 +16,7 @@
 #include "qemu/osdep.h"
 #include "qapi/error.h"
 #include "hw/virtio/vhost.h"
+#include "hw/virtio/virtio-dmabuf.h"
 #include "qemu/atomic.h"
 #include "qemu/range.h"
 #include "qemu/error-report.h"
@@ -1599,6 +1600,8 @@ void vhost_dev_cleanup(struct vhost_dev *hdev)
     migrate_del_blocker(&hdev->migration_blocker);
     g_free(hdev->mem);
     g_free(hdev->mem_sections);
+    /* free virtio shared objects */
+    virtio_dmabuf_vhost_cleanup(hdev);
     if (hdev->vhost_ops) {
         hdev->vhost_ops->vhost_backend_cleanup(hdev);
     }
diff --git a/include/hw/virtio/virtio-dmabuf.h b/include/hw/virtio/virtio-dmabuf.h
index 627c3b6db7..73f70fb482 100644
--- a/include/hw/virtio/virtio-dmabuf.h
+++ b/include/hw/virtio/virtio-dmabuf.h
@@ -91,6 +91,16 @@ struct vhost_dev *virtio_lookup_vhost_device(const QemuUUID *uuid);
  */
 SharedObjectType virtio_object_type(const QemuUUID *uuid);
 
+/**
+ * virtio_dmabuf_vhost_cleanup() - Destroys all entries of the shared
+ * resources lookup table that are owned by the vhost backend
+ * @dev: the pointer to the vhost device that owns the entries. Data is owned
+ *       by the called of the function.
+ * 
+ * Return: the number of resource entries removed.
+ */
+int virtio_dmabuf_vhost_cleanup(struct vhost_dev *dev);
+
 /**
  * virtio_free_resources() - Destroys all keys and values of the shared
  * resources lookup table, and frees them
diff --git a/tests/unit/test-virtio-dmabuf.c b/tests/unit/test-virtio-dmabuf.c
index a45ec52f42..1c8123c2d2 100644
--- a/tests/unit/test-virtio-dmabuf.c
+++ b/tests/unit/test-virtio-dmabuf.c
@@ -103,6 +103,38 @@ static void test_add_invalid_resource(void)
     }
 }
 
+static void test_cleanup_res(void)
+{
+    QemuUUID uuids[20], uuid_alt;
+    struct vhost_dev *dev = g_new0(struct vhost_dev, 1);
+    struct vhost_dev *dev_alt = g_new0(struct vhost_dev, 1);
+    int i, num_removed;
+
+    for (i = 0; i < ARRAY_SIZE(uuids); ++i) {
+        qemu_uuid_generate(&uuids[i]);
+        virtio_add_vhost_device(&uuids[i], dev);
+        /* vhost device is found */
+        g_assert(virtio_lookup_vhost_device(&uuids[i]) != NULL);
+    }
+    qemu_uuid_generate(&uuid_alt);
+    virtio_add_vhost_device(&uuid_alt, dev_alt);
+    /* vhost device is found */
+    g_assert(virtio_lookup_vhost_device(&uuid_alt) != NULL);
+    /* cleanup all dev resources */
+    num_removed = virtio_dmabuf_vhost_cleanup(dev);
+    g_assert_cmpint(num_removed, ==, ARRAY_SIZE(uuids));
+    for (i = 0; i < ARRAY_SIZE(uuids); ++i) {
+        /* None of the dev resources is found after free'd */
+        g_assert_cmpint(virtio_lookup_dmabuf(&uuids[i]), ==, -1);
+    }
+    /* uuid_alt is still in the hash table */
+    g_assert(virtio_lookup_vhost_device(&uuid_alt) != NULL);
+
+    virtio_free_resources();
+    g_free(dev);
+    g_free(dev_alt);
+}
+
 static void test_free_resources(void)
 {
     QemuUUID uuids[20];
@@ -131,6 +163,7 @@ int main(int argc, char **argv)
                     test_remove_invalid_resource);
     g_test_add_func("/virtio-dmabuf/add_invalid_res",
                     test_add_invalid_resource);
+    g_test_add_func("/virtio-dmabuf/cleanup_dev", test_cleanup_res);
     g_test_add_func("/virtio-dmabuf/free_res", test_free_resources);
 
     return g_test_run();
-- 
2.43.0

[PATCH v2 3/3] hw/virtio: rename virtio dmabuf API

[Albert Esteve]

Functions in the virtio-dmabuf module
start with 'virtio_*', which is too
generic and may not correctly identify
them as part of the virtio dmabuf API.

Rename all functions to 'virtio_dmabuf_*'
instead to avoid confusion.

Signed-off-by: Albert Esteve <aesteve@redhat.com>
---
 hw/display/virtio-dmabuf.c        | 14 +++++-----
 hw/virtio/vhost-user.c            | 14 +++++-----
 include/hw/virtio/virtio-dmabuf.h | 33 ++++++++++++-----------
 tests/unit/test-virtio-dmabuf.c   | 44 +++++++++++++++----------------
 4 files changed, 53 insertions(+), 52 deletions(-)

diff --git a/hw/display/virtio-dmabuf.c b/hw/display/virtio-dmabuf.c
index 6688809777..42495f87ec 100644
--- a/hw/display/virtio-dmabuf.c
+++ b/hw/display/virtio-dmabuf.c
@@ -48,7 +48,7 @@ static bool virtio_add_resource(QemuUUID *uuid, VirtioSharedObject *value)
     return result;
 }
 
-bool virtio_add_dmabuf(QemuUUID *uuid, int udmabuf_fd)
+bool virtio_dmabuf_add(QemuUUID *uuid, int udmabuf_fd)
 {
     bool result;
     VirtioSharedObject *vso;
@@ -66,7 +66,7 @@ bool virtio_add_dmabuf(QemuUUID *uuid, int udmabuf_fd)
     return result;
 }
 
-bool virtio_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev)
+bool virtio_dmabuf_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev)
 {
     bool result;
     VirtioSharedObject *vso;
@@ -84,7 +84,7 @@ bool virtio_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev)
     return result;
 }
 
-bool virtio_remove_resource(const QemuUUID *uuid)
+bool virtio_dmabuf_remove_resource(const QemuUUID *uuid)
 {
     bool result;
     g_mutex_lock(&lock);
@@ -107,7 +107,7 @@ static VirtioSharedObject *get_shared_object(const QemuUUID *uuid)
     return (VirtioSharedObject *) lookup_res;
 }
 
-int virtio_lookup_dmabuf(const QemuUUID *uuid)
+int virtio_dmabuf_lookup(const QemuUUID *uuid)
 {
     VirtioSharedObject *vso = get_shared_object(uuid);
     if (vso == NULL) {
@@ -117,7 +117,7 @@ int virtio_lookup_dmabuf(const QemuUUID *uuid)
     return GPOINTER_TO_INT(vso->value);
 }
 
-struct vhost_dev *virtio_lookup_vhost_device(const QemuUUID *uuid)
+struct vhost_dev *virtio_dmabuf_lookup_vhost_device(const QemuUUID *uuid)
 {
     VirtioSharedObject *vso = get_shared_object(uuid);
     if (vso == NULL) {
@@ -127,7 +127,7 @@ struct vhost_dev *virtio_lookup_vhost_device(const QemuUUID *uuid)
     return (struct vhost_dev *) vso->value;
 }
 
-SharedObjectType virtio_object_type(const QemuUUID *uuid)
+SharedObjectType virtio_dmabuf_object_type(const QemuUUID *uuid)
 {
     VirtioSharedObject *vso = get_shared_object(uuid);
     if (vso == NULL) {
@@ -158,7 +158,7 @@ int virtio_dmabuf_vhost_cleanup(struct vhost_dev *dev)
     return num_removed;
 }
 
-void virtio_free_resources(void)
+void virtio_dmabuf_free_resources(void)
 {
     g_mutex_lock(&lock);
     g_hash_table_destroy(resource_uuids);
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 1c3f2357be..2ab9e13f9e 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -1607,7 +1607,7 @@ vhost_user_backend_handle_shared_object_add(struct vhost_dev *dev,
     QemuUUID uuid;
 
     memcpy(uuid.data, object->uuid, sizeof(object->uuid));
-    return virtio_add_vhost_device(&uuid, dev);
+    return virtio_dmabuf_add_vhost_device(&uuid, dev);
 }
 
 static int
@@ -1617,10 +1617,10 @@ vhost_user_backend_handle_shared_object_remove(struct vhost_dev *dev,
     QemuUUID uuid;
 
     memcpy(uuid.data, object->uuid, sizeof(object->uuid));
-    switch (virtio_object_type(&uuid)) {
+    switch (virtio_dmabuf_object_type(&uuid)) {
     case TYPE_VHOST_DEV:
     {
-        struct vhost_dev *owner = virtio_lookup_vhost_device(&uuid);
+        struct vhost_dev *owner = virtio_dmabuf_lookup_vhost_device(&uuid);
         if (owner == NULL || dev != owner) {
             /* Not allowed to remove non-owned entries */
             return 0;
@@ -1632,7 +1632,7 @@ vhost_user_backend_handle_shared_object_remove(struct vhost_dev *dev,
         return 0;
     }
 
-    return virtio_remove_resource(&uuid);
+    return virtio_dmabuf_remove_resource(&uuid);
 }
 
 static bool vhost_user_send_resp(QIOChannel *ioc, VhostUserHeader *hdr,
@@ -1710,13 +1710,13 @@ vhost_user_backend_handle_shared_object_lookup(struct vhost_user *u,
     memcpy(uuid.data, payload->object.uuid, sizeof(payload->object.uuid));
 
     payload->u64 = 0;
-    switch (virtio_object_type(&uuid)) {
+    switch (virtio_dmabuf_object_type(&uuid)) {
     case TYPE_DMABUF:
-        dmabuf_fd = virtio_lookup_dmabuf(&uuid);
+        dmabuf_fd = virtio_dmabuf_lookup(&uuid);
         break;
     case TYPE_VHOST_DEV:
     {
-        struct vhost_dev *dev = virtio_lookup_vhost_device(&uuid);
+        struct vhost_dev *dev = virtio_dmabuf_lookup_vhost_device(&uuid);
         if (dev == NULL) {
             payload->u64 = -EINVAL;
             break;
diff --git a/include/hw/virtio/virtio-dmabuf.h b/include/hw/virtio/virtio-dmabuf.h
index 73f70fb482..186a18a33b 100644
--- a/include/hw/virtio/virtio-dmabuf.h
+++ b/include/hw/virtio/virtio-dmabuf.h
@@ -28,7 +28,7 @@ typedef struct VirtioSharedObject {
 } VirtioSharedObject;
 
 /**
- * virtio_add_dmabuf() - Add a new dma-buf resource to the lookup table
+ * virtio_dmabuf_add() - Add a new dma-buf resource to the lookup table
  * @uuid: new resource's UUID
  * @dmabuf_fd: the dma-buf descriptor that will be stored and shared with
  *             other virtio devices. The caller retains ownership over the
@@ -41,11 +41,11 @@ typedef struct VirtioSharedObject {
  * Note that if it finds a repeated UUID, the resource is not inserted in
  * the lookup table.
  */
-bool virtio_add_dmabuf(QemuUUID *uuid, int dmabuf_fd);
+bool virtio_dmabuf_add(QemuUUID *uuid, int dmabuf_fd);
 
 /**
- * virtio_add_vhost_device() - Add a new exporter vhost device that holds the
- * resource with the associated UUID
+ * virtio_dmabuf_add_vhost_device() - Add a new exporter vhost device that
+ * holds the resource with the associated UUID
  * @uuid: new resource's UUID
  * @dev: the pointer to the vhost device that holds the resource. The caller
  *       retains ownership over the device struct and its lifecycle.
@@ -55,41 +55,42 @@ bool virtio_add_dmabuf(QemuUUID *uuid, int dmabuf_fd);
  * Note that if it finds a repeated UUID, the resource is not inserted in
  * the lookup table.
  */
-bool virtio_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev);
+bool virtio_dmabuf_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev);
 
 /**
- * virtio_remove_resource() - Removes a resource from the lookup table
+ * virtio_dmabuf_remove_resource() - Removes a resource from the lookup table
  * @uuid: resource's UUID
  *
  * Return: true if the UUID has been found and removed from the lookup table.
  */
-bool virtio_remove_resource(const QemuUUID *uuid);
+bool virtio_dmabuf_remove_resource(const QemuUUID *uuid);
 
 /**
- * virtio_lookup_dmabuf() - Looks for a dma-buf resource in the lookup table
+ * virtio_dmabuf_lookup() - Looks for a dma-buf resource in the lookup table
  * @uuid: resource's UUID
  *
  * Return: the dma-buf file descriptor integer, or -1 if the key is not found.
  */
-int virtio_lookup_dmabuf(const QemuUUID *uuid);
+int virtio_dmabuf_lookup(const QemuUUID *uuid);
 
 /**
- * virtio_lookup_vhost_device() - Looks for an exporter vhost device in the
- * lookup table
+ * virtio_dmabuf_lookup_vhost_device() - Looks for an exporter vhost device
+ * in the lookup table
  * @uuid: resource's UUID
  *
  * Return: pointer to the vhost_dev struct, or NULL if the key is not found.
  */
-struct vhost_dev *virtio_lookup_vhost_device(const QemuUUID *uuid);
+struct vhost_dev *virtio_dmabuf_lookup_vhost_device(const QemuUUID *uuid);
 
 /**
- * virtio_object_type() - Looks for the type of resource in the lookup table
+ * virtio_dmabuf_object_type() - Looks for the type of resource in the
+ * lookup table
  * @uuid: resource's UUID
  *
  * Return: the type of resource associated with the UUID, or TYPE_INVALID if
  * the key is not found.
  */
-SharedObjectType virtio_object_type(const QemuUUID *uuid);
+SharedObjectType virtio_dmabuf_object_type(const QemuUUID *uuid);
 
 /**
  * virtio_dmabuf_vhost_cleanup() - Destroys all entries of the shared
@@ -102,9 +103,9 @@ SharedObjectType virtio_object_type(const QemuUUID *uuid);
 int virtio_dmabuf_vhost_cleanup(struct vhost_dev *dev);
 
 /**
- * virtio_free_resources() - Destroys all keys and values of the shared
+ * virtio_dmabuf_free_resources() - Destroys all keys and values of the shared
  * resources lookup table, and frees them
  */
-void virtio_free_resources(void);
+void virtio_dmabuf_free_resources(void);
 
 #endif /* VIRTIO_DMABUF_H */
diff --git a/tests/unit/test-virtio-dmabuf.c b/tests/unit/test-virtio-dmabuf.c
index 1c8123c2d2..7471ed4fbd 100644
--- a/tests/unit/test-virtio-dmabuf.c
+++ b/tests/unit/test-virtio-dmabuf.c
@@ -31,12 +31,12 @@ static void test_add_remove_resources(void)
         qemu_uuid_generate(&uuid);
         dmabuf_fd = g_random_int_range(3, 500);
         /* Add a new resource */
-        g_assert(virtio_add_dmabuf(&uuid, dmabuf_fd));
-        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, dmabuf_fd);
+        g_assert(virtio_dmabuf_add(&uuid, dmabuf_fd));
+        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, dmabuf_fd);
         /* Remove the resource */
-        g_assert(virtio_remove_resource(&uuid));
+        g_assert(virtio_dmabuf_remove_resource(&uuid));
         /* Resource is not found anymore */
-        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, -1);
+        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, -1);
     }
 }
 
@@ -48,13 +48,13 @@ static void test_add_remove_dev(void)
 
     for (i = 0; i < 100; ++i) {
         qemu_uuid_generate(&uuid);
-        virtio_add_vhost_device(&uuid, dev);
+        virtio_dmabuf_add_vhost_device(&uuid, dev);
         /* vhost device is found */
-        g_assert(virtio_lookup_vhost_device(&uuid) != NULL);
+        g_assert(virtio_dmabuf_lookup_vhost_device(&uuid) != NULL);
         /* Remove the vhost device */
-        g_assert(virtio_remove_resource(&uuid));
+        g_assert(virtio_dmabuf_remove_resource(&uuid));
         /* vhost device is not found anymore */
-        g_assert(virtio_lookup_vhost_device(&uuid) == NULL);
+        g_assert(virtio_dmabuf_lookup_vhost_device(&uuid) == NULL);
     }
     g_free(dev);
 }
@@ -66,9 +66,9 @@ static void test_remove_invalid_resource(void)
 
     for (i = 0; i < 20; ++i) {
         qemu_uuid_generate(&uuid);
-        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, -1);
+        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, -1);
         /* Removing a resource that does not exist returns false */
-        g_assert_false(virtio_remove_resource(&uuid));
+        g_assert_false(virtio_dmabuf_remove_resource(&uuid));
     }
 }
 
@@ -81,25 +81,25 @@ static void test_add_invalid_resource(void)
     for (i = 0; i < 20; ++i) {
         qemu_uuid_generate(&uuid);
         /* Add a new resource with invalid (negative) resource fd */
-        g_assert_false(virtio_add_dmabuf(&uuid, dmabuf_fd));
+        g_assert_false(virtio_dmabuf_add(&uuid, dmabuf_fd));
         /* Resource is not found */
-        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, -1);
+        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, -1);
         /* Add a new vhost device with invalid (NULL) pointer */
-        g_assert_false(virtio_add_vhost_device(&uuid, dev));
+        g_assert_false(virtio_dmabuf_add_vhost_device(&uuid, dev));
         /* vhost device is not found */
-        g_assert(virtio_lookup_vhost_device(&uuid) == NULL);
+        g_assert(virtio_dmabuf_lookup_vhost_device(&uuid) == NULL);
     }
 
     for (i = 0; i < 20; ++i) {
         /* Add a valid resource */
         qemu_uuid_generate(&uuid);
         dmabuf_fd = g_random_int_range(3, 500);
-        g_assert(virtio_add_dmabuf(&uuid, dmabuf_fd));
-        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, dmabuf_fd);
+        g_assert(virtio_dmabuf_add(&uuid, dmabuf_fd));
+        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, dmabuf_fd);
         /* Add a new resource with repeated uuid returns false */
-        g_assert_false(virtio_add_dmabuf(&uuid, alt_dmabuf));
+        g_assert_false(virtio_dmabuf_add(&uuid, alt_dmabuf));
         /* The value for the uuid key is not replaced */
-        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, dmabuf_fd);
+        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, dmabuf_fd);
     }
 }
 
@@ -143,13 +143,13 @@ static void test_free_resources(void)
     for (i = 0; i < ARRAY_SIZE(uuids); ++i) {
         qemu_uuid_generate(&uuids[i]);
         dmabuf_fd = g_random_int_range(3, 500);
-        g_assert(virtio_add_dmabuf(&uuids[i], dmabuf_fd));
-        g_assert_cmpint(virtio_lookup_dmabuf(&uuids[i]), ==, dmabuf_fd);
+        g_assert(virtio_dmabuf_add(&uuids[i], dmabuf_fd));
+        g_assert_cmpint(virtio_dmabuf_lookup(&uuids[i]), ==, dmabuf_fd);
     }
-    virtio_free_resources();
+    virtio_dmabuf_free_resources();
     for (i = 0; i < ARRAY_SIZE(uuids); ++i) {
         /* None of the resources is found after free'd */
-        g_assert_cmpint(virtio_lookup_dmabuf(&uuids[i]), ==, -1);
+        g_assert_cmpint(virtio_dmabuf_lookup(&uuids[i]), ==, -1);
     }
 
 }
-- 
2.43.0

Re: [PATCH v2 3/3] hw/virtio: rename virtio dmabuf API

[Albert Esteve]

[-- Attachment #1: Type: text/plain, Size: 14619 bytes --]

On Thu, Dec 7, 2023 at 3:55 PM Albert Esteve <aesteve@redhat.com> wrote:

> Functions in the virtio-dmabuf module
> start with 'virtio_*', which is too
> generic and may not correctly identify
> them as part of the virtio dmabuf API.
>
> Rename all functions to 'virtio_dmabuf_*'
> instead to avoid confusion.
>
> Signed-off-by: Albert Esteve <aesteve@redhat.com>
> ---
>  hw/display/virtio-dmabuf.c        | 14 +++++-----
>  hw/virtio/vhost-user.c            | 14 +++++-----
>  include/hw/virtio/virtio-dmabuf.h | 33 ++++++++++++-----------
>  tests/unit/test-virtio-dmabuf.c   | 44 +++++++++++++++----------------
>  4 files changed, 53 insertions(+), 52 deletions(-)
>
> diff --git a/hw/display/virtio-dmabuf.c b/hw/display/virtio-dmabuf.c
> index 6688809777..42495f87ec 100644
> --- a/hw/display/virtio-dmabuf.c
> +++ b/hw/display/virtio-dmabuf.c
> @@ -48,7 +48,7 @@ static bool virtio_add_resource(QemuUUID *uuid,
> VirtioSharedObject *value)
>      return result;
>  }
>
> -bool virtio_add_dmabuf(QemuUUID *uuid, int udmabuf_fd)
> +bool virtio_dmabuf_add(QemuUUID *uuid, int udmabuf_fd)
>  {
>      bool result;
>      VirtioSharedObject *vso;
> @@ -66,7 +66,7 @@ bool virtio_add_dmabuf(QemuUUID *uuid, int udmabuf_fd)
>      return result;
>  }
>
> -bool virtio_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev)
> +bool virtio_dmabuf_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev)
>  {
>      bool result;
>      VirtioSharedObject *vso;
> @@ -84,7 +84,7 @@ bool virtio_add_vhost_device(QemuUUID *uuid, struct
> vhost_dev *dev)
>      return result;
>  }
>
> -bool virtio_remove_resource(const QemuUUID *uuid)
> +bool virtio_dmabuf_remove_resource(const QemuUUID *uuid)
>  {
>      bool result;
>      g_mutex_lock(&lock);
> @@ -107,7 +107,7 @@ static VirtioSharedObject *get_shared_object(const
> QemuUUID *uuid)
>      return (VirtioSharedObject *) lookup_res;
>  }
>
> -int virtio_lookup_dmabuf(const QemuUUID *uuid)
> +int virtio_dmabuf_lookup(const QemuUUID *uuid)
>  {
>      VirtioSharedObject *vso = get_shared_object(uuid);
>      if (vso == NULL) {
> @@ -117,7 +117,7 @@ int virtio_lookup_dmabuf(const QemuUUID *uuid)
>      return GPOINTER_TO_INT(vso->value);
>  }
>
> -struct vhost_dev *virtio_lookup_vhost_device(const QemuUUID *uuid)
> +struct vhost_dev *virtio_dmabuf_lookup_vhost_device(const QemuUUID *uuid)
>  {
>      VirtioSharedObject *vso = get_shared_object(uuid);
>      if (vso == NULL) {
> @@ -127,7 +127,7 @@ struct vhost_dev *virtio_lookup_vhost_device(const
> QemuUUID *uuid)
>      return (struct vhost_dev *) vso->value;
>  }
>
> -SharedObjectType virtio_object_type(const QemuUUID *uuid)
> +SharedObjectType virtio_dmabuf_object_type(const QemuUUID *uuid)
>  {
>      VirtioSharedObject *vso = get_shared_object(uuid);
>      if (vso == NULL) {
> @@ -158,7 +158,7 @@ int virtio_dmabuf_vhost_cleanup(struct vhost_dev *dev)
>      return num_removed;
>  }
>
> -void virtio_free_resources(void)
> +void virtio_dmabuf_free_resources(void)
>  {
>      g_mutex_lock(&lock);
>      g_hash_table_destroy(resource_uuids);
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index 1c3f2357be..2ab9e13f9e 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -1607,7 +1607,7 @@ vhost_user_backend_handle_shared_object_add(struct
> vhost_dev *dev,
>      QemuUUID uuid;
>
>      memcpy(uuid.data, object->uuid, sizeof(object->uuid));
> -    return virtio_add_vhost_device(&uuid, dev);
> +    return virtio_dmabuf_add_vhost_device(&uuid, dev);
>  }
>
>  static int
> @@ -1617,10 +1617,10 @@
> vhost_user_backend_handle_shared_object_remove(struct vhost_dev *dev,
>      QemuUUID uuid;
>
>      memcpy(uuid.data, object->uuid, sizeof(object->uuid));
> -    switch (virtio_object_type(&uuid)) {
> +    switch (virtio_dmabuf_object_type(&uuid)) {
>      case TYPE_VHOST_DEV:
>      {
> -        struct vhost_dev *owner = virtio_lookup_vhost_device(&uuid);
> +        struct vhost_dev *owner =
> virtio_dmabuf_lookup_vhost_device(&uuid);
>          if (owner == NULL || dev != owner) {
>              /* Not allowed to remove non-owned entries */
>              return 0;
> @@ -1632,7 +1632,7 @@
> vhost_user_backend_handle_shared_object_remove(struct vhost_dev *dev,
>          return 0;
>      }
>
> -    return virtio_remove_resource(&uuid);
> +    return virtio_dmabuf_remove_resource(&uuid);
>  }
>
>  static bool vhost_user_send_resp(QIOChannel *ioc, VhostUserHeader *hdr,
> @@ -1710,13 +1710,13 @@
> vhost_user_backend_handle_shared_object_lookup(struct vhost_user *u,
>      memcpy(uuid.data, payload->object.uuid, sizeof(payload->object.uuid));
>
>      payload->u64 = 0;
> -    switch (virtio_object_type(&uuid)) {
> +    switch (virtio_dmabuf_object_type(&uuid)) {
>      case TYPE_DMABUF:
> -        dmabuf_fd = virtio_lookup_dmabuf(&uuid);
> +        dmabuf_fd = virtio_dmabuf_lookup(&uuid);
>          break;
>      case TYPE_VHOST_DEV:
>      {
> -        struct vhost_dev *dev = virtio_lookup_vhost_device(&uuid);
> +        struct vhost_dev *dev = virtio_dmabuf_lookup_vhost_device(&uuid);
>          if (dev == NULL) {
>              payload->u64 = -EINVAL;
>              break;
> diff --git a/include/hw/virtio/virtio-dmabuf.h
> b/include/hw/virtio/virtio-dmabuf.h
> index 73f70fb482..186a18a33b 100644
> --- a/include/hw/virtio/virtio-dmabuf.h
> +++ b/include/hw/virtio/virtio-dmabuf.h
> @@ -28,7 +28,7 @@ typedef struct VirtioSharedObject {
>  } VirtioSharedObject;
>
>  /**
> - * virtio_add_dmabuf() - Add a new dma-buf resource to the lookup table
> + * virtio_dmabuf_add() - Add a new dma-buf resource to the lookup table
>   * @uuid: new resource's UUID
>   * @dmabuf_fd: the dma-buf descriptor that will be stored and shared with
>   *             other virtio devices. The caller retains ownership over the
> @@ -41,11 +41,11 @@ typedef struct VirtioSharedObject {
>   * Note that if it finds a repeated UUID, the resource is not inserted in
>   * the lookup table.
>   */
> -bool virtio_add_dmabuf(QemuUUID *uuid, int dmabuf_fd);
> +bool virtio_dmabuf_add(QemuUUID *uuid, int dmabuf_fd);
>
>  /**
> - * virtio_add_vhost_device() - Add a new exporter vhost device that holds
> the
> - * resource with the associated UUID
> + * virtio_dmabuf_add_vhost_device() - Add a new exporter vhost device that
> + * holds the resource with the associated UUID
>   * @uuid: new resource's UUID
>   * @dev: the pointer to the vhost device that holds the resource. The
> caller
>   *       retains ownership over the device struct and its lifecycle.
> @@ -55,41 +55,42 @@ bool virtio_add_dmabuf(QemuUUID *uuid, int dmabuf_fd);
>   * Note that if it finds a repeated UUID, the resource is not inserted in
>   * the lookup table.
>   */
> -bool virtio_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev);
> +bool virtio_dmabuf_add_vhost_device(QemuUUID *uuid, struct vhost_dev
> *dev);
>
>  /**
> - * virtio_remove_resource() - Removes a resource from the lookup table
> + * virtio_dmabuf_remove_resource() - Removes a resource from the lookup
> table
>   * @uuid: resource's UUID
>   *
>   * Return: true if the UUID has been found and removed from the lookup
> table.
>   */
> -bool virtio_remove_resource(const QemuUUID *uuid);
> +bool virtio_dmabuf_remove_resource(const QemuUUID *uuid);
>
>  /**
> - * virtio_lookup_dmabuf() - Looks for a dma-buf resource in the lookup
> table
> + * virtio_dmabuf_lookup() - Looks for a dma-buf resource in the lookup
> table
>   * @uuid: resource's UUID
>   *
>   * Return: the dma-buf file descriptor integer, or -1 if the key is not
> found.
>   */
> -int virtio_lookup_dmabuf(const QemuUUID *uuid);
> +int virtio_dmabuf_lookup(const QemuUUID *uuid);
>
>  /**
> - * virtio_lookup_vhost_device() - Looks for an exporter vhost device in
> the
> - * lookup table
> + * virtio_dmabuf_lookup_vhost_device() - Looks for an exporter vhost
> device
> + * in the lookup table
>   * @uuid: resource's UUID
>   *
>   * Return: pointer to the vhost_dev struct, or NULL if the key is not
> found.
>   */
> -struct vhost_dev *virtio_lookup_vhost_device(const QemuUUID *uuid);
> +struct vhost_dev *virtio_dmabuf_lookup_vhost_device(const QemuUUID *uuid);
>
>  /**
> - * virtio_object_type() - Looks for the type of resource in the lookup
> table
> + * virtio_dmabuf_object_type() - Looks for the type of resource in the
> + * lookup table
>   * @uuid: resource's UUID
>   *
>   * Return: the type of resource associated with the UUID, or TYPE_INVALID
> if
>   * the key is not found.
>   */
> -SharedObjectType virtio_object_type(const QemuUUID *uuid);
> +SharedObjectType virtio_dmabuf_object_type(const QemuUUID *uuid);
>
>  /**
>   * virtio_dmabuf_vhost_cleanup() - Destroys all entries of the shared
> @@ -102,9 +103,9 @@ SharedObjectType virtio_object_type(const QemuUUID
> *uuid);
>  int virtio_dmabuf_vhost_cleanup(struct vhost_dev *dev);
>
>  /**
> - * virtio_free_resources() - Destroys all keys and values of the shared
> + * virtio_dmabuf_free_resources() - Destroys all keys and values of the
> shared
>   * resources lookup table, and frees them
>   */
> -void virtio_free_resources(void);
> +void virtio_dmabuf_free_resources(void);
>
>  #endif /* VIRTIO_DMABUF_H */
> diff --git a/tests/unit/test-virtio-dmabuf.c
> b/tests/unit/test-virtio-dmabuf.c
> index 1c8123c2d2..7471ed4fbd 100644
> --- a/tests/unit/test-virtio-dmabuf.c
> +++ b/tests/unit/test-virtio-dmabuf.c
> @@ -31,12 +31,12 @@ static void test_add_remove_resources(void)
>          qemu_uuid_generate(&uuid);
>          dmabuf_fd = g_random_int_range(3, 500);
>          /* Add a new resource */
> -        g_assert(virtio_add_dmabuf(&uuid, dmabuf_fd));
> -        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, dmabuf_fd);
> +        g_assert(virtio_dmabuf_add(&uuid, dmabuf_fd));
> +        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, dmabuf_fd);
>          /* Remove the resource */
> -        g_assert(virtio_remove_resource(&uuid));
> +        g_assert(virtio_dmabuf_remove_resource(&uuid));
>          /* Resource is not found anymore */
> -        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, -1);
> +        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, -1);
>      }
>  }
>
> @@ -48,13 +48,13 @@ static void test_add_remove_dev(void)
>
>      for (i = 0; i < 100; ++i) {
>          qemu_uuid_generate(&uuid);
> -        virtio_add_vhost_device(&uuid, dev);
> +        virtio_dmabuf_add_vhost_device(&uuid, dev);
>          /* vhost device is found */
> -        g_assert(virtio_lookup_vhost_device(&uuid) != NULL);
> +        g_assert(virtio_dmabuf_lookup_vhost_device(&uuid) != NULL);
>          /* Remove the vhost device */
> -        g_assert(virtio_remove_resource(&uuid));
> +        g_assert(virtio_dmabuf_remove_resource(&uuid));
>          /* vhost device is not found anymore */
> -        g_assert(virtio_lookup_vhost_device(&uuid) == NULL);
> +        g_assert(virtio_dmabuf_lookup_vhost_device(&uuid) == NULL);
>      }
>      g_free(dev);
>  }
> @@ -66,9 +66,9 @@ static void test_remove_invalid_resource(void)
>
>      for (i = 0; i < 20; ++i) {
>          qemu_uuid_generate(&uuid);
> -        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, -1);
> +        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, -1);
>          /* Removing a resource that does not exist returns false */
> -        g_assert_false(virtio_remove_resource(&uuid));
> +        g_assert_false(virtio_dmabuf_remove_resource(&uuid));
>      }
>  }
>
> @@ -81,25 +81,25 @@ static void test_add_invalid_resource(void)
>      for (i = 0; i < 20; ++i) {
>          qemu_uuid_generate(&uuid);
>          /* Add a new resource with invalid (negative) resource fd */
> -        g_assert_false(virtio_add_dmabuf(&uuid, dmabuf_fd));
> +        g_assert_false(virtio_dmabuf_add(&uuid, dmabuf_fd));
>          /* Resource is not found */
> -        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, -1);
> +        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, -1);
>          /* Add a new vhost device with invalid (NULL) pointer */
> -        g_assert_false(virtio_add_vhost_device(&uuid, dev));
> +        g_assert_false(virtio_dmabuf_add_vhost_device(&uuid, dev));
>          /* vhost device is not found */
> -        g_assert(virtio_lookup_vhost_device(&uuid) == NULL);
> +        g_assert(virtio_dmabuf_lookup_vhost_device(&uuid) == NULL);
>      }
>
>      for (i = 0; i < 20; ++i) {
>          /* Add a valid resource */
>          qemu_uuid_generate(&uuid);
>          dmabuf_fd = g_random_int_range(3, 500);
> -        g_assert(virtio_add_dmabuf(&uuid, dmabuf_fd));
> -        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, dmabuf_fd);
> +        g_assert(virtio_dmabuf_add(&uuid, dmabuf_fd));
> +        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, dmabuf_fd);
>          /* Add a new resource with repeated uuid returns false */
> -        g_assert_false(virtio_add_dmabuf(&uuid, alt_dmabuf));
> +        g_assert_false(virtio_dmabuf_add(&uuid, alt_dmabuf));
>          /* The value for the uuid key is not replaced */
> -        g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, dmabuf_fd);
> +        g_assert_cmpint(virtio_dmabuf_lookup(&uuid), ==, dmabuf_fd);
>      }
>  }
>
> @@ -143,13 +143,13 @@ static void test_free_resources(void)
>      for (i = 0; i < ARRAY_SIZE(uuids); ++i) {
>          qemu_uuid_generate(&uuids[i]);
>          dmabuf_fd = g_random_int_range(3, 500);
> -        g_assert(virtio_add_dmabuf(&uuids[i], dmabuf_fd));
> -        g_assert_cmpint(virtio_lookup_dmabuf(&uuids[i]), ==, dmabuf_fd);
> +        g_assert(virtio_dmabuf_add(&uuids[i], dmabuf_fd));
> +        g_assert_cmpint(virtio_dmabuf_lookup(&uuids[i]), ==, dmabuf_fd);
>      }
> -    virtio_free_resources();
> +    virtio_dmabuf_free_resources();
>      for (i = 0; i < ARRAY_SIZE(uuids); ++i) {
>          /* None of the resources is found after free'd */
> -        g_assert_cmpint(virtio_lookup_dmabuf(&uuids[i]), ==, -1);
> +        g_assert_cmpint(virtio_dmabuf_lookup(&uuids[i]), ==, -1);
>      }
>
>  }
> --
> 2.43.0
>
>
Agh I forgot to rename the function in the new test after applying the last
review.
I have it fixed in my local branch and passing the tests. I'll wait for
feedback
on the other commits and push a new version after.

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Re: [PATCH v2 0/3] Virtio dmabuf improvements

[Stefan Hajnoczi]

On Thu, 7 Dec 2023 at 09:55, Albert Esteve <aesteve@redhat.com> wrote:
>
> v1: https://www.mail-archive.com/qemu-devel@nongnu.org/msg1005257.html
> v1 -> v2:
>   - Solved an unitialized uuid value on vhost-user source
>   - Changed cleanup strategy, and traverse all objects in the
>     table to remove them instead.

Please update the vhost-user specification
(docs/interop/vhost-user.rst) so people implementing front-ends and
back-ends are aware that only the back-end that added a shared
resource can remove it.

Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

>
> Various improvements for the virtio-dmabuf module.
> This patch includes:
>
> - Check for ownership before allowing a vhost device
>   to remove an object from the table.
> - Properly cleanup shared resources if a vhost device
>   object gets cleaned up.
> - Rename virtio dmabuf functions to `virtio_dmabuf_*`
>
> Albert Esteve (3):
>   hw/virtio: check owner for removing objects
>   hw/virtio: cleanup shared resources
>   hw/virtio: rename virtio dmabuf API
>
>  hw/display/virtio-dmabuf.c        | 36 ++++++++++++---
>  hw/virtio/vhost-user.c            | 31 ++++++++++---
>  hw/virtio/vhost.c                 |  3 ++
>  include/hw/virtio/virtio-dmabuf.h | 43 ++++++++++-------
>  tests/unit/test-virtio-dmabuf.c   | 77 ++++++++++++++++++++++---------
>  5 files changed, 138 insertions(+), 52 deletions(-)
>
> --
> 2.43.0
>

Re: [PATCH v2 0/3] Virtio dmabuf improvements

[Albert Esteve]

[-- Attachment #1: Type: text/plain, Size: 1765 bytes --]

On Mon, Dec 11, 2023 at 10:48 PM Stefan Hajnoczi <stefanha@gmail.com> wrote:

> On Thu, 7 Dec 2023 at 09:55, Albert Esteve <aesteve@redhat.com> wrote:
> >
> > v1: https://www.mail-archive.com/qemu-devel@nongnu.org/msg1005257.html
> > v1 -> v2:
> >   - Solved an unitialized uuid value on vhost-user source
> >   - Changed cleanup strategy, and traverse all objects in the
> >     table to remove them instead.
>
> Please update the vhost-user specification
> (docs/interop/vhost-user.rst) so people implementing front-ends and
> back-ends are aware that only the back-end that added a shared
> resource can remove it.
>
> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
>
>
Will do :)

Should I add the `Acked-by` manually to the commits or does it
get automatically picked up later?

BR,
Albert

PS: Happy New Year!


> >
> > Various improvements for the virtio-dmabuf module.
> > This patch includes:
> >
> > - Check for ownership before allowing a vhost device
> >   to remove an object from the table.
> > - Properly cleanup shared resources if a vhost device
> >   object gets cleaned up.
> > - Rename virtio dmabuf functions to `virtio_dmabuf_*`
> >
> > Albert Esteve (3):
> >   hw/virtio: check owner for removing objects
> >   hw/virtio: cleanup shared resources
> >   hw/virtio: rename virtio dmabuf API
> >
> >  hw/display/virtio-dmabuf.c        | 36 ++++++++++++---
> >  hw/virtio/vhost-user.c            | 31 ++++++++++---
> >  hw/virtio/vhost.c                 |  3 ++
> >  include/hw/virtio/virtio-dmabuf.h | 43 ++++++++++-------
> >  tests/unit/test-virtio-dmabuf.c   | 77 ++++++++++++++++++++++---------
> >  5 files changed, 138 insertions(+), 52 deletions(-)
> >
> > --
> > 2.43.0
> >
>
>

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Re: [PATCH v2 0/3] Virtio dmabuf improvements

[Stefan Hajnoczi]

On Mon, 8 Jan 2024 at 10:49, Albert Esteve <aesteve@redhat.com> wrote:
> On Mon, Dec 11, 2023 at 10:48 PM Stefan Hajnoczi <stefanha@gmail.com> wrote:
>>
>> On Thu, 7 Dec 2023 at 09:55, Albert Esteve <aesteve@redhat.com> wrote:
>> >
>> > v1: https://www.mail-archive.com/qemu-devel@nongnu.org/msg1005257.html
>> > v1 -> v2:
>> >   - Solved an unitialized uuid value on vhost-user source
>> >   - Changed cleanup strategy, and traverse all objects in the
>> >     table to remove them instead.
>>
>> Please update the vhost-user specification
>> (docs/interop/vhost-user.rst) so people implementing front-ends and
>> back-ends are aware that only the back-end that added a shared
>> resource can remove it.
>>
>> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
>>
>
> Will do :)
>
> Should I add the `Acked-by` manually to the commits or does it get automatically picked up later?

Happy New Year! When a patch series is merged then the maintainer
usually (automatically) picks up trailers from the latest revision on
the mailing list. Trailers from earlier revisions may not be present.

When you respin the patch series then you can add trailers manually
with git rebase -i by adding "x git commit --no-edit
--trailer='Acked-by: Stefan Hajnoczi <stefanha@redhat.com>'" lines in
between each commit in the rebase list.

Stefan