xen: make earlyprintk=xen work again

For some perverse reason, if you call add_preferred_console() it prevents
setup_early_printk() from successfully enabling the boot console -
unless you make it a preferred console too...

Also, make xenboot console output distinct from normal console output,
since it gets repeated when the console handover happens, and the
duplicated output is confusing without disambiguation.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>

2 files changed, 2 insertions, 0 deletions

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 6cfb708408e9..5c0635a8bffd 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1257,6 +1257,7 @@ asmlinkage void __init xen_start_kernel(void)
         boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
 
         if (!is_initial_xendomain()) {
+                add_preferred_console("xenboot", 0, NULL);
                 add_preferred_console("tty", 0, NULL);
                 add_preferred_console("hvc", 0, NULL);
         }
diff --git a/drivers/char/hvc_xen.c b/drivers/char/hvc_xen.c
index 2413af342a81..d5fe0a8952fa 100644
--- a/drivers/char/hvc_xen.c
+++ b/drivers/char/hvc_xen.c
@@ -155,6 +155,7 @@ static void xenboot_write_console(struct console *console, const char *string,
 
         raw_console_write(string, len);
 
+        write_console(0, "(early) ", 8);
         while (off < len && NULL != (pos = strchr(string+off, '\n'))) {
                 linelen = pos-string+off;
                 if (off + linelen > len)