[PATCH net v3 3/3] vsock: document write-once behavior of the child_ns_mode sysctl

[Bobby Eshleman]

From: Bobby Eshleman <bobbyeshleman@xxxxxxxx>

Update the vsock child_ns_mode documentation to include the new
write-once semantics of setting child_ns_mode. The semantics are
implemented in a preceding patch in this series.

Signed-off-by: Bobby Eshleman <bobbyeshleman@xxxxxxxx>
---
Changes in v3:
- update language to clarify language that first value is locked, but subsequent
  writes succeed.
---
 Documentation/admin-guide/sysctl/net.rst | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/admin-guide/sysctl/net.rst b/Documentation/admin-guide/sysctl/net.rst
index c10530624f1e..3b2ad61995d4 100644
--- a/Documentation/admin-guide/sysctl/net.rst
+++ b/Documentation/admin-guide/sysctl/net.rst
@@ -594,6 +594,9 @@ Values:
 	  their sockets will only be able to connect within their own
 	  namespace.
 
+The first write to ``child_ns_mode`` locks its value. Subsequent writes of the
+same value succeed, but writing a different value returns ``-EBUSY``.
+
 Changing ``child_ns_mode`` only affects namespaces created after the change;
 it does not modify the current namespace or any existing children.
 

-- 
2.47.3