diff --git a/Cargo.lock b/Cargo.lock
index 7d2e8ba3..5521ceb4 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -27,7 +27,7 @@ dependencies = [
  "spin 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "uart_16550 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "volatile 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "x86_64 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "x86_64 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -47,6 +47,11 @@ name = "cast"
 version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "cc"
+version = "1.0.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "fixedvec"
 version = "0.2.4"
@@ -70,6 +75,37 @@ name = "nodrop"
 version = "0.1.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "raw-cpuid"
+version = "6.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cc 1.0.37 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rustc_version"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "semver"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "semver-parser"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "spin"
 version = "0.4.10"
@@ -106,7 +142,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "x86_64"
-version = "0.7.4"
+version = "0.5.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "array-init 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -119,6 +155,7 @@ dependencies = [
 
 [[package]]
 name = "x86_64"
+version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "array-init 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -147,17 +184,22 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3d155346769a6855b86399e9bc3814ab343cd3d62c7e985113d46a0ec3c281fd"
 "checksum bootloader 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)" = "b15e5b7b9d9a8e427cf4270894f51ce288632a3a1a2cc6f8fda669d5446f98bd"
 "checksum cast 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "926013f2860c46252efceabb19f4a6b308197505082c609025aa6706c011d427"
+"checksum cc 1.0.37 (registry+https://github.com/rust-lang/crates.io-index)" = "39f75544d7bbaf57560d2168f28fd649ff9c76153874db88bdbdfd839b1a7e7d"
 "checksum fixedvec 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "b395ef2adf62bdeefcd1b59ad0dd2225c6c333ec79656ea79ac5285c46d051ea"
 "checksum lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bc5729f27f159ddd61f4df6228e827e86643d4d3e7c32183cb30a1c08f604a14"
 "checksum llvm-tools 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "955be5d0ca0465caf127165acb47964f911e2bc26073e865deb8be7189302faf"
 "checksum nodrop 0.1.13 (registry+https://github.com/rust-lang/crates.io-index)" = "2f9667ddcc6cc8a43afc9b7917599d7216aa09c463919ea32c59ed6cac8bc945"
+"checksum raw-cpuid 6.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "30a9d219c32c9132f7be513c18be77c9881c7107d2ab5569d205a6a0f0e6dc7d"
+"checksum rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
+"checksum semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1d7eb9ef2c18661902cc47e535f9bc51b78acd254da71d375c2f6720d9a40403"
+"checksum semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
 "checksum spin 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)" = "ceac490aa12c567115b40b7b7fceca03a6c9d53d5defea066123debc83c5dc1f"
 "checksum spin 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "44363f6f51401c34e7be73db0db371c04705d35efbe9f7d6082e03a921a32c55"
 "checksum uart_16550 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5b9392f60931fe3bf8f24e0a15ee4f51528770f1d64c48768ab66571334d95b0"
 "checksum usize_conversions 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f70329e2cbe45d6c97a5112daad40c34cd9a4e18edb5a2a18fefeb584d8d25e5"
 "checksum ux 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "88dfeb711b61ce620c0cb6fd9f8e3e678622f0c971da2a63c4b3e25e88ed012f"
 "checksum volatile 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "6af0edf5b4faacc31fc51159244d78d65ec580f021afcef7bd53c04aeabc7f29"
-"checksum x86_64 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)" = "1ad37c1665071808d64e65f7cdae32afcdc90fd7ae7fa402bbda36b824f1add6"
 "checksum x86_64 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)" = "bb8f09c32a991cc758ebcb9b7984f530095d32578a4e7b85db6ee1f0bbe4c9c6"
+"checksum x86_64 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)" = "1ad37c1665071808d64e65f7cdae32afcdc90fd7ae7fa402bbda36b824f1add6"
 "checksum xmas-elf 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "22678df5df766e8d1e5d609da69f0c3132d794edf6ab5e75e7abcd2270d4cf58"
 "checksum zero 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "5f1bc8a6b2005884962297587045002d8cfb8dcec9db332f4ca216ddc5de82c5"