diff --git a/src/main.rs b/src/main.rs
index 360643b60..43d98445c 100755
--- a/src/main.rs
+++ b/src/main.rs
@@ -195,10 +195,7 @@ fn create_app<'a, 'b>(
         .arg(
             Arg::with_name("vsock")
                 .long("vsock")
-                .help(
-                    "Virtio VSOCK parameters \
-                    \"cid=<context_id>,sock=<socket_path>,iommu=on|off,id=<device_id>\"",
-                )
+                .help(config::VsockConfig::SYNTAX)
                 .takes_value(true)
                 .number_of_values(1)
                 .group("vm-config"),
diff --git a/vmm/src/config.rs b/vmm/src/config.rs
index 6161c6a1d..f9b9e2928 100644
--- a/vmm/src/config.rs
+++ b/vmm/src/config.rs
@@ -1141,6 +1141,8 @@ pub struct VsockConfig {
 }
 
 impl VsockConfig {
+    pub const SYNTAX: &'static str = "Virtio VSOCK parameters \
+        \"cid=<context_id>,sock=<socket_path>,iommu=on|off,id=<device_id>\"";
     pub fn parse(vsock: &str) -> Result<Self> {
         let mut parser = OptionParser::new();
         parser.add("sock").add("cid").add("iommu").add("id");