diff --git a/apps/microtvm/zephyr/demo_runtime/src/main.c b/apps/microtvm/zephyr/demo_runtime/src/main.c
index 4074d18b045ae..2e05b31bb575f 100644
--- a/apps/microtvm/zephyr/demo_runtime/src/main.c
+++ b/apps/microtvm/zephyr/demo_runtime/src/main.c
@@ -216,35 +216,37 @@ tvm_crt_error_t TVMPlatformTimerStop(double* elapsed_time_seconds) {
 }
 
 // Ring buffer used to store data read from the UART on rx interrupt.
-#define RING_BUF_SIZE_BYTES TVM_CRT_MAX_PACKET_SIZE_BYTES
-RING_BUF_ITEM_DECLARE_SIZE(uart_rx_rbuf, TVM_CRT_MAX_PACKET_SIZE_BYTES);
+#define RING_BUF_SIZE_BYTES (TVM_CRT_MAX_PACKET_SIZE_BYTES + 22)
+RING_BUF_ITEM_DECLARE_SIZE(uart_rx_rbuf, RING_BUF_SIZE_BYTES);
 
 // UART interrupt callback.
 void uart_irq_cb(const struct device* dev, void* user_data) {
   uart_irq_update(dev);
-  struct ring_buf* rbuf = (struct ring_buf*)user_data;
-  if (uart_irq_rx_ready(dev) != 0) {
-    uint8_t* data;
-    uint32_t size;
-    size = ring_buf_put_claim(rbuf, &data, RING_BUF_SIZE_BYTES);
-    int rx_size = uart_fifo_read(dev, data, size);
-    // Write it into the ring buffer.
-    g_num_bytes_in_rx_buffer += rx_size;
-    if (g_num_bytes_in_rx_buffer > RING_BUF_SIZE_BYTES) {
-      TVMLogf("Ring buffer overflow. (%d > %d)", g_num_bytes_in_rx_buffer, RING_BUF_SIZE_BYTES);
-      TVMPlatformAbort((tvm_crt_error_t)0xbeef3);
-    }
+  if (uart_irq_is_pending(dev)) {
+    struct ring_buf* rbuf = (struct ring_buf*)user_data;
+    if (uart_irq_rx_ready(dev) != 0) {
+      uint8_t* data;
+      uint32_t size;
+      size = ring_buf_put_claim(rbuf, &data, RING_BUF_SIZE_BYTES);
+      int rx_size = uart_fifo_read(dev, data, size);
+      // Write it into the ring buffer.
+      g_num_bytes_in_rx_buffer += rx_size;
+
+      if (g_num_bytes_in_rx_buffer > RING_BUF_SIZE_BYTES) {
+        TVMPlatformAbort((tvm_crt_error_t)0xbeef3);
+      }
 
-    if (rx_size < 0) {
-      TVMPlatformAbort((tvm_crt_error_t)0xbeef1);
-    }
+      if (rx_size < 0) {
+        TVMPlatformAbort((tvm_crt_error_t)0xbeef1);
+      }
 
-    int err = ring_buf_put_finish(rbuf, rx_size);
-    if (err != 0) {
-      TVMPlatformAbort((tvm_crt_error_t)0xbeef2);
+      int err = ring_buf_put_finish(rbuf, rx_size);
+      if (err != 0) {
+        TVMPlatformAbort((tvm_crt_error_t)0xbeef2);
+      }
+      // CHECK_EQ(bytes_read, bytes_written, "bytes_read: %d; bytes_written: %d", bytes_read,
+      // bytes_written);
     }
-    // CHECK_EQ(bytes_read, bytes_written, "bytes_read: %d; bytes_written: %d", bytes_read,
-    // bytes_written);
   }
 }
 
@@ -311,7 +313,10 @@ void main(void) {
           g_num_bytes_requested = 0;
         }
       }
-      ring_buf_get_finish(&uart_rx_rbuf, bytes_read);
+      int err = ring_buf_get_finish(&uart_rx_rbuf, bytes_read);
+      if (err != 0) {
+        TVMPlatformAbort((tvm_crt_error_t)0xbeef6);
+      }
     }
     irq_unlock(key);
   }