diff --git a/WHATS_NEW b/WHATS_NEW
index 97bd68089..ed1b37fd7 100644
--- a/WHATS_NEW
+++ b/WHATS_NEW
@@ -1,5 +1,6 @@
 Version 2.02.97 - 
 ===============================
+  Use 64bit math for reserved memory and stack.
   Add tests for kernel_send() errors in cmirrod.
   Print clean_bits in pull_state, fix cut&paste typo in cmirrord.
   Add tests for errors from closedir(), close() in cmirrord.
diff --git a/lib/mm/memlock.c b/lib/mm/memlock.c
index 8c631bf44..17dee1c90 100644
--- a/lib/mm/memlock.c
+++ b/lib/mm/memlock.c
@@ -446,12 +446,12 @@ void memlock_dec_daemon(struct cmd_context *cmd)
 void memlock_init(struct cmd_context *cmd)
 {
 	/* When threaded, caller already limited stack size so just use the default. */
-	_size_stack = 1024 * (cmd->threaded ? DEFAULT_RESERVED_STACK :
-					      find_config_tree_int(cmd, "activation/reserved_stack",
-								   DEFAULT_RESERVED_STACK));
+	_size_stack = 1024ULL * (cmd->threaded ? DEFAULT_RESERVED_STACK :
+				 find_config_tree_int(cmd, "activation/reserved_stack",
+						      DEFAULT_RESERVED_STACK));
 	_size_malloc_tmp = find_config_tree_int(cmd,
 					   "activation/reserved_memory",
-					   DEFAULT_RESERVED_MEMORY) * 1024;
+					   DEFAULT_RESERVED_MEMORY) * 1024ULL;
 	_default_priority = find_config_tree_int(cmd,
 					    "activation/process_priority",
 					    DEFAULT_PROCESS_PRIORITY);