Document the fact that VTY locking is easily bypassable when DDB

is compiled in the kernel.  Also add some useful xrefs to lock(1).

1 files changed, 4 insertions, 0 deletions

diff --git a/usr.sbin/vidcontrol/vidcontrol.1 b/usr.sbin/vidcontrol/vidcontrol.1
index edde901..63252c0 100644
--- a/usr.sbin/vidcontrol/vidcontrol.1
+++ b/usr.sbin/vidcontrol/vidcontrol.1
@@ -228,6 +228,10 @@ Turn vty switching on or off.
 When vty switching is off,
 attempts to switch to a different virtual terminal will fail.
 (The default is to permit vty switching.)
+This protection can be easily bypassed when the kernel is compiled with
+the DDB option.
+However, you probably shouldn't compile the kernel debugger on a box which
+is supposed to be physically secure.
 .It Fl s Ar number
 Set the current vty to
 .Ar number .