diff --git a/Cargo.toml b/Cargo.toml
index 57683b58..a3820dcf 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,7 +9,7 @@ bootloader = "0.3.12"
 spin = "0.4.9"
 volatile = "0.2.3"
 uart_16550 = "0.1.0"
-x86_64 = "0.3.5"
+x86_64 = "0.4.0"
 pic8259_simple = "0.1.1"
 pc-keyboard = "0.3.1"
 
diff --git a/blog/content/second-edition/posts/05-integration-tests/index.md b/blog/content/second-edition/posts/05-integration-tests/index.md
index ea0d07ed..6f3596dc 100644
--- a/blog/content/second-edition/posts/05-integration-tests/index.md
+++ b/blog/content/second-edition/posts/05-integration-tests/index.md
@@ -198,7 +198,7 @@ To write to the I/O port, we use the [`x86_64`] crate:
 # in Cargo.toml
 
 [dependencies]
-x86_64 = "0.3.5"
+x86_64 = "0.4.0"
 ```
 
 ```rust