diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 363e348bff9b93598587710de952a22c89f12bbe..69f97a83660058b1a036051db3e86da2bfc63576 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2248,6 +2248,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 				the default.
 				off: Turn ECRC off
 				on: Turn ECRC on.
+		hpiosize=nn[KMG]	The fixed amount of bus space which is
+				reserved for hotplug bridge's IO window.
+				Default size is 256 bytes.
+		hpmemsize=nn[KMG]	The fixed amount of bus space which is
+				reserved for hotplug bridge's memory window.
+				Default size is 2 megabytes.
 		realloc=	Enable/disable reallocating PCI bridge resources
 				if allocations done by BIOS are too small to
 				accommodate resources required by all child