diff --git a/src/arch/x86_shared/gdt.rs b/src/arch/x86_shared/gdt.rs
index 3c5b32c2dd..64912a55ff 100644
--- a/src/arch/x86_shared/gdt.rs
+++ b/src/arch/x86_shared/gdt.rs
@@ -240,7 +240,7 @@ pub unsafe fn set_tss_stack(pcr: *mut ProcessorControlRegion, stack: usize) {
 
 pub unsafe fn set_userspace_io_allowed(pcr: *mut ProcessorControlRegion, allowed: bool) {
     let offset = if allowed {
-        u16::try_from(size_of::<TaskStateSegment>()).unwrap()
+        u16::try_from(size_of::<TaskStateSegment>()).expect("guaranteed to fit in u16")
     } else {
         0xFFFF
     };
diff --git a/src/context/context.rs b/src/context/context.rs
index 8481524f21..a174124458 100644
--- a/src/context/context.rs
+++ b/src/context/context.rs
@@ -513,7 +513,7 @@ impl BorrowedHtBuf {
     }
     */
 
-    pub fn into_drop(mut self, token: &mut CleanLockToken) {
+    pub fn into_drop(self, token: &mut CleanLockToken) {
         ManuallyDrop::new(self).inner_drop(token);
     }
 
diff --git a/src/sync/wait_condition.rs b/src/sync/wait_condition.rs
index 47df00a5dd..6c7a59fd51 100644
--- a/src/sync/wait_condition.rs
+++ b/src/sync/wait_condition.rs
@@ -127,7 +127,7 @@ impl WaitCondition {
         waited
     }
 
-    pub fn into_drop(mut self, token: &mut CleanLockToken) {
+    pub fn into_drop(self, token: &mut CleanLockToken) {
         ManuallyDrop::new(self).inner_drop(token);
     }