diff --git a/firmware/Cargo.lock b/firmware/Cargo.lock
index 61241a8..131130b 100644
--- a/firmware/Cargo.lock
+++ b/firmware/Cargo.lock
@@ -2,29 +2,23 @@
 name = "ionpak-firmware"
 version = "0.1.0"
 dependencies = [
- "cortex-m 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "cortex-m-rt 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cortex-m 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cortex-m-rt 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "tm4c129x 0.4.0 (git+https://github.com/m-labs/dslite2svd)",
 ]
 
 [[package]]
 name = "cortex-m"
-version = "0.2.4"
-source = "git+https://github.com/whitequark/cortex-m?rev=fpu-cpacr#0e3dd2df58e52f9af80e47327a62a83511e010f9"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cortex-m-semihosting 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "volatile-register 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "cortex-m"
-version = "0.2.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-replace = "cortex-m 0.2.4 (git+https://github.com/whitequark/cortex-m?rev=fpu-cpacr)"
-
 [[package]]
 name = "cortex-m-rt"
-version = "0.2.0"
+version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "r0 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -45,7 +39,7 @@ name = "tm4c129x"
 version = "0.4.0"
 source = "git+https://github.com/m-labs/dslite2svd#43d3964bb9dcebe631b0bdf1c2fdc975cf53c41c"
 dependencies = [
- "cortex-m 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cortex-m 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "vcell 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -63,9 +57,8 @@ dependencies = [
 ]
 
 [metadata]
-"checksum cortex-m 0.2.4 (git+https://github.com/whitequark/cortex-m?rev=fpu-cpacr)" = "<none>"
-"checksum cortex-m 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "964f183322128497a636a5d4524dfe91fa1394a15b7b2c4329ee5bb66bef1548"
-"checksum cortex-m-rt 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2ed494cbd15190fae60f608e6b4690e753df47b5f5e25e95d3c298f801f5c1d0"
+"checksum cortex-m 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)" = "56f002db38ab2c7a829bc0b997db8c5f47ada08f88a248c729d4f73c555628db"
+"checksum cortex-m-rt 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0db3cf185ad88e3d70e9b7738d1bad23f86322130d376df9b80a64df7abdb4cb"
 "checksum cortex-m-semihosting 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "54a88e8fd577808637f819107f34eece1b6b45be8db1c56d1c563095b80b655e"
 "checksum r0 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "6e7bbed8cd0a245bbf3759ebb35c964822b7a8c15ceeeee56d4cc5f060ce518e"
 "checksum tm4c129x 0.4.0 (git+https://github.com/m-labs/dslite2svd)" = "<none>"
diff --git a/firmware/Cargo.toml b/firmware/Cargo.toml
index 25984d5..53412ac 100644
--- a/firmware/Cargo.toml
+++ b/firmware/Cargo.toml
@@ -4,13 +4,10 @@ version = "0.1.0"
 authors = ["whitequark <whitequark@whitequark.org>"]
 
 [dependencies]
-cortex-m = "0.2.4"
+cortex-m = "0.2.5"
 cortex-m-rt = { version = "0.2.0", features = ["linker-script"], default-features = false }
 tm4c129x = { git = "https://github.com/m-labs/dslite2svd" }
 
 [profile.release]
 lto = true
 debug = true
-
-[replace]
-"cortex-m:0.2.4" = { git = "https://github.com/whitequark/cortex-m", rev = "fpu-cpacr" }
diff --git a/firmware/src/main.rs b/firmware/src/main.rs
index 887eab1..d197db6 100644
--- a/firmware/src/main.rs
+++ b/firmware/src/main.rs
@@ -121,7 +121,7 @@ fn error_reset() {
 
 
 fn main() {
-    cortex_m::interrupt::enable();
+    unsafe { cortex_m::interrupt::enable(); }
     cortex_m::interrupt::free(|cs| {
         let sysctl = tm4c129x::SYSCTL.borrow(cs);
         let nvic = tm4c129x::NVIC.borrow(cs);