diff --git a/hmp-commands.hx b/hmp-commands.hx
index 0de7c4c29e..754620e411 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1116,7 +1116,7 @@ ETEXI
 
     {
         .name       = "dump-guest-memory",
-        .args_type  = "paging:-p,detach:-d,zlib:-z,lzo:-l,snappy:-s,filename:F,begin:i?,length:i?",
+        .args_type  = "paging:-p,detach:-d,zlib:-z,lzo:-l,snappy:-s,filename:F,begin:l?,length:l?",
         .params     = "[-p] [-d] [-z|-l|-s] filename [begin length]",
         .help       = "dump guest memory into file 'filename'.\n\t\t\t"
                       "-p: do paging to get guest's memory mapping.\n\t\t\t"