[PATCH] uml: mconsole locking

Locking fixes.  Locking was totally lacking for the mconsole_devices, which
got a spin lock, and the unplugged pages data, which got a mutex.

The locking of the mconsole console output code was confused.  Now, the
console_lock (renamed to client_lock) protects the clients list.

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>

arch/um/kernel/tt/gdb_kern.c

@@ -12,6 +12,7 @@ extern int gdb_config(char *str, char **error_out);
 extern int gdb_remove(int n, char **error_out);
 
 static struct mc_device gdb_mc = {
+	.list		= INIT_LIST_HEAD(gdb_mc.list),
 	.name		= "gdb",
 	.config		= gdb_config,
 	.remove		= gdb_remove,