diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index e9261e9..c357a31 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -872,6 +872,12 @@
 			       If specified, z/VM IUCV HVC accepts connections
 			       from listed z/VM user IDs only.
 
+	keep_bootcon	[KNL]
+			Do not unregister boot console at start. This is only
+			useful for debugging when something happens in the window
+			between unregistering the boot console and initializing
+			the real console.
+
 	i2c_bus=	[HW] Override the default board specific I2C bus speed
 			     or register an additional I2C bus that is not
 			     registered from board initialization code.
diff --git a/kernel/printk.c b/kernel/printk.c
index 33284ad..2b591f2 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -1316,6 +1316,18 @@
 }
 EXPORT_SYMBOL(console_start);
 
+static int __read_mostly keep_bootcon;
+
+static int __init keep_bootcon_setup(char *str)
+{
+	keep_bootcon = 1;
+	printk(KERN_INFO "debug: skip boot console de-registration.\n");
+
+	return 0;
+}
+
+early_param("keep_bootcon", keep_bootcon_setup);
+
 /*
  * The console driver calls this routine during kernel initialization
  * to register the console printing procedure with printk() and to
@@ -1463,7 +1475,9 @@
 	 * users know there might be something in the kernel's log buffer that
 	 * went to the bootconsole (that they do not see on the real console)
 	 */
-	if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV)) {
+	if (bcon &&
+	    ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV) &&
+	    !keep_bootcon) {
 		/* we need to iterate through twice, to make sure we print
 		 * everything out, before we unregister the console(s)
 		 */