diff --git a/vulkan/nulldrv/null_driver.cpp b/vulkan/nulldrv/null_driver.cpp
index 8f47bd1..9462a3e 100644
--- a/vulkan/nulldrv/null_driver.cpp
+++ b/vulkan/nulldrv/null_driver.cpp
@@ -89,7 +89,7 @@
 };
 }  // namespace HandleType
 
-const VkDeviceSize kMaxDeviceMemory = VkDeviceSize(INTPTR_MAX) + 1;
+const VkDeviceSize kMaxDeviceMemory = 0x10000000;  // 256 MiB, arbitrary
 
 }  // anonymous namespace
 
diff --git a/vulkan/tools/vkinfo.cpp b/vulkan/tools/vkinfo.cpp
index 462a8e5..9cbd234 100644
--- a/vulkan/tools/vkinfo.cpp
+++ b/vulkan/tools/vkinfo.cpp
@@ -342,7 +342,7 @@
             strbuf << "DEVICE_LOCAL";
         printf("%sHeap %u: %" PRIu64 " MiB (0x%" PRIx64 " B) %s\n",
                Indent(indent + 1), heap,
-               info.memory.memoryHeaps[heap].size / 0x1000000,
+               info.memory.memoryHeaps[heap].size / 0x100000,
                info.memory.memoryHeaps[heap].size, strbuf.str().c_str());
         strbuf.str(std::string());