diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index 016a047cfc..8c9d80e9fe 100644
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -390,7 +390,8 @@ void os_mem_prealloc(int fd, char *area, size_t memory)
     pthread_sigmask(SIG_UNBLOCK, &set, &oldset);
 
     if (sigsetjmp(sigjump, 1)) {
-        fprintf(stderr, "os_mem_prealloc: failed to preallocate pages\n");
+        fprintf(stderr, "os_mem_prealloc: Insufficient free host memory "
+                        "pages available to allocate guest RAM\n");
         exit(1);
     } else {
         int i;