[PATCH] uml: umid tidying

Add an error message when two umids are put on the command line.

umid.h is kind of pointless since it only declares one thing, and that
is already declared in os.h.

Commented the lack of locking of some data in os-Linux/umid.h.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/um/os-Linux/umid.c b/arch/um/os-Linux/umid.c
index 48092b9..b462863 100644
--- a/arch/um/os-Linux/umid.c
+++ b/arch/um/os-Linux/umid.c
@@ -18,7 +18,7 @@
 #define UMID_LEN 64
 
 /* Changed by set_umid, which is run early in boot */
-char umid[UMID_LEN] = { 0 };
+static char umid[UMID_LEN] = { 0 };
 
 /* Changed by set_uml_dir and make_uml_dir, which are run early in boot */
 static char *uml_dir = UML_DIR;
@@ -235,6 +235,7 @@
 	return 0;
 }
 
+/* Changed in make_umid, which is called during early boot */
 static int umid_setup = 0;
 
 int __init make_umid(void)