Console: introduce console=none command line parameter

Currenty, not specifying 'console=<foo>' on the command line causes
Xen to default to 'vga'.  Alternativly, the user can explicitly
specifiy 'console=vga|com1|com2'.

However, there is no way to specify that neither vga nor serial should
be used.  Specifying 'console=' does have the effect that neither vga
nor serial is set up, but at the cost of an "Bad console= option ''"
warning.

Therefore, expliticly support a 'console=none' option which does not
set up vga and does not set up serial, but does not trigger the bad
console warning.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Committed-by: Keir Fraser <keir@xen.org>
xen-unstable changeset:   24614:f8c2cf24a26c
xen-unstable date:        Sat Jan 28 13:41:42 2012 +0000

diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c
index 92ab60d2823ce65021386f409f221190f32385bc..bd574612c50ea852ad530e7f14983195b931175f 100644 (file)
--- a/xen/drivers/char/console.c
+++ b/xen/drivers/char/console.c
@@ -557,6 +557,8 @@ void __init console_init_preirq(void)
             p++;
         if ( !strncmp(p, "vga", 3) )
             vga_init();
+        else if ( !strncmp(p, "none", 4) )
+            continue;
         else if ( strncmp(p, "com", 3) ||
                   (sercon_handle = serial_parse_handle(p)) == -1 )
         {