diff --git a/src/context/list.rs b/src/context/list.rs
index dc11536..a745955 100644
--- a/src/context/list.rs
+++ b/src/context/list.rs
@@ -80,13 +80,11 @@ impl ContextList {
         {
             let mut context = context_lock.write();
             let mut fx = unsafe {
-                let ptr = crate::ALLOCATOR.alloc(Layout::from_size_align_unchecked(1024, 16)) as *mut [u8; 1024];
+                // TODO: Alignment must match, the following can be UB. Use AlignedBox.
+                let ptr = crate::ALLOCATOR.alloc_zeroed(Layout::from_size_align_unchecked(1024, 16)) as *mut [u8; 1024];
                 if ptr.is_null() { return Err(Error::new(ENOMEM)); }
                 Box::from_raw(ptr)
             };
-            for b in fx.iter_mut() {
-                *b = 0;
-            }
             let mut stack = vec![0; 65_536].into_boxed_slice();
             let offset = stack.len() - mem::size_of::<usize>();
 
diff --git a/src/context/mod.rs b/src/context/mod.rs
index 9268b14..6b80e0f 100644
--- a/src/context/mod.rs
+++ b/src/context/mod.rs
@@ -57,10 +57,12 @@ pub fn init() {
     let mut contexts = contexts_mut();
     let context_lock = contexts.new_context().expect("could not initialize first context");
     let mut context = context_lock.write();
-    let mut fx = unsafe { Box::from_raw(crate::ALLOCATOR.alloc(Layout::from_size_align_unchecked(1024, 16)) as *mut [u8; 1024]) };
-    for b in fx.iter_mut() {
-        *b = 0;
-    }
+    let fx = unsafe {
+        // TODO: Alignment must match, the following can be UB. Use AlignedBox.
+        let ptr = crate::ALLOCATOR.alloc_zeroed(Layout::from_size_align_unchecked(1024, 16)) as *mut [u8; 1024];
+        assert!(!ptr.is_null(), "failed to allocate FX to kmain!");
+        Box::from_raw(ptr)
+    };
 
     context.arch.set_fx(fx.as_ptr() as usize);
     context.kfx = Some(fx);