diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 97ed3bd9707f..2dd254c720f5 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -211,7 +211,7 @@ MODULE_PARM_DESC(discard, "Support discard operations (requires memory-backed nu
 
 static unsigned long g_cache_size;
 module_param_named(cache_size, g_cache_size, ulong, 0444);
-MODULE_PARM_DESC(mbps, "Cache size in MiB for memory-backed device. Default: 0 (none)");
+MODULE_PARM_DESC(cache_size, "Cache size in MiB for memory-backed device. Default: 0 (none)");
 
 static unsigned int g_mbps;
 module_param_named(mbps, g_mbps, uint, 0444);