diff --git a/samples/rust/rust_driver_faux.rs b/samples/rust/rust_driver_faux.rs
index de131fce491a..6db3124ed3a9 100644
--- a/samples/rust/rust_driver_faux.rs
+++ b/samples/rust/rust_driver_faux.rs
@@ -2,8 +2,10 @@
 
 //! Rust faux device sample.
 
+use core::cell::Cell;
 use kernel::{
     faux,
+    fmt,
     prelude::*,
     Module, //
 };
@@ -20,6 +22,20 @@ struct SampleModule {
     _reg: faux::Registration,
 }
 
+struct Status<'a>(&'a Cell<usize>);
+
+impl fmt::Display for Status<'_> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.set(self.0.get() + 1);
+        f.write_str("ready")
+    }
+}
+
+fn read_status<'a>(reads: &Cell<usize>, formats: &'a Cell<usize>) -> Status<'a> {
+    reads.set(reads.get() + 1);
+    Status(formats)
+}
+
 impl Module for SampleModule {
     fn init(_module: &'static ThisModule) -> Result<Self> {
         pr_info!("Initialising Rust Faux Device Sample\n");
@@ -30,6 +46,28 @@ fn init(_module: &'static ThisModule) -> Result<Self> {
         dev_info!(fdev, "Hello from faux device!\n");
         dev_dbg!(fdev, "foobar\n");
 
+        let reads = Cell::new(0);
+        let formats = Cell::new(0);
+        pr_debug!("dyndbg repro pr: {}\n", read_status(&reads, &formats));
+        pr_info!(
+            "dyndbg repro pr: args={} fmt={}\n",
+            reads.get(),
+            formats.get()
+        );
+
+        reads.set(0);
+        formats.set(0);
+        dev_dbg!(
+            fdev,
+            "dyndbg repro dev: {}\n",
+            read_status(&reads, &formats)
+        );
+        pr_info!(
+            "dyndbg repro dev: args={} fmt={}\n",
+            reads.get(),
+            formats.get()
+        );
+
         Ok(Self { _reg: reg })
     }
 }
-- 
2.53.0