diff --git a/src/xhyve.c b/src/xhyve.c
index 97fd41f..f69e6ea 100644
--- a/src/xhyve.c
+++ b/src/xhyve.c
@@ -135,7 +135,7 @@ usage(int code)
 		"       -h: help\n"
 		"       -H: vmexit from the guest on hlt\n"
 		"       -l: LPC device configuration\n"
-		"       -m: memory size in MB\n"
+		"       -m: memory size in MB, may be suffixed with one of K, M, G or T\n"
 		"       -p: pin 'vcpu' to 'hostcpu'\n"
 		"       -P: vmexit from the guest on pause\n"
 		"       -s: <slot,driver,configinfo> PCI slot config\n"