Planes can have name, create a plane attribute to configure it. Currently
plane name is mainly used in logs.

Signed-off-by: Louis Chauvet <[email protected]>
---
 Documentation/ABI/testing/configfs-vkms |  6 +++++
 Documentation/gpu/vkms.rst              |  3 ++-
 drivers/gpu/drm/vkms/vkms_configfs.c    | 43 +++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/configfs-vkms 
b/Documentation/ABI/testing/configfs-vkms
index 0beaa25f30ba..6fe375d1636f 100644
--- a/Documentation/ABI/testing/configfs-vkms
+++ b/Documentation/ABI/testing/configfs-vkms
@@ -103,6 +103,12 @@ Description:
         Plane type. Possible values: 0 - overlay, 1 - primary,
         2 - cursor.
 
+What:          /sys/kernel/config/vkms/<device>/planes/<plane>/name
+Date:          Nov 2025
+Contact:       [email protected]
+Description:
+        Name of the plane.
+
 What:          /sys/kernel/config/vkms/<device>/planes/<plane>/possible_crtcs
 Date:          Nov 2025
 Contact:       [email protected]
diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
index 1e79e62a6bc4..79f1185d8645 100644
--- a/Documentation/gpu/vkms.rst
+++ b/Documentation/gpu/vkms.rst
@@ -87,10 +87,11 @@ Start by creating one or more planes::
 
   sudo mkdir /config/vkms/my-vkms/planes/plane0
 
-Planes have 1 configurable attribute:
+Planes have 2 configurable attributes:
 
 - type: Plane type: 0 overlay, 1 primary, 2 cursor (same values as those
   exposed by the "type" property of a plane)
+- name: Name of the plane. Allowed characters are [A-Za-z1-9_-]
 
 Continue by creating one or more CRTCs::
 
diff --git a/drivers/gpu/drm/vkms/vkms_configfs.c 
b/drivers/gpu/drm/vkms/vkms_configfs.c
index 506666e21c91..989788042191 100644
--- a/drivers/gpu/drm/vkms/vkms_configfs.c
+++ b/drivers/gpu/drm/vkms/vkms_configfs.c
@@ -324,10 +324,53 @@ static ssize_t plane_type_store(struct config_item *item, 
const char *page,
        return (ssize_t)count;
 }
 
+static ssize_t plane_name_show(struct config_item *item, char *page)
+{
+       struct vkms_configfs_plane *plane;
+       const char *name;
+
+       plane = plane_item_to_vkms_configfs_plane(item);
+
+       scoped_guard(mutex, &plane->dev->lock)
+               name = vkms_config_plane_get_name(plane->config);
+
+       if (name)
+               return sprintf(page, "%s\n", name);
+       return sprintf(page, "\n");
+}
+
+static ssize_t plane_name_store(struct config_item *item, const char *page,
+                               size_t count)
+{
+       struct vkms_configfs_plane *plane;
+       size_t str_len;
+
+       plane = plane_item_to_vkms_configfs_plane(item);
+
+       // strspn is not lenght-protected, ensure that page is a 
null-terminated string.
+       str_len = strnlen(page, count);
+       if (str_len >= count)
+               return -EINVAL;
+
+       if (strspn(page, 
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_-") != count - 
1)
+               return -EINVAL;
+
+       scoped_guard(mutex, &plane->dev->lock) {
+               if (plane->dev->enabled)
+                       return -EBUSY;
+
+               vkms_config_plane_set_name(plane->config, page);
+       }
+
+       return (ssize_t)count;
+}
+
 CONFIGFS_ATTR(plane_, type);
+CONFIGFS_ATTR(plane_, name);
 
 static struct configfs_attribute *plane_item_attrs[] = {
        &plane_attr_type,
+       &plane_attr_name,
        NULL,
 };
 

-- 
2.51.2

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