diff --git a/virtio-devices/src/balloon.rs b/virtio-devices/src/balloon.rs
index 640ef7f21..89bea794e 100644
--- a/virtio-devices/src/balloon.rs
+++ b/virtio-devices/src/balloon.rs
@@ -321,8 +321,10 @@ impl Balloon {
     pub fn new(id: String, size: u64, seccomp_action: SeccompAction) -> io::Result<Self> {
         let avail_features = 1u64 << VIRTIO_F_VERSION_1;
 
-        let mut config = VirtioBalloonConfig::default();
-        config.num_pages = (size >> VIRTIO_BALLOON_PFN_SHIFT) as u32;
+        let config = VirtioBalloonConfig {
+            num_pages: (size >> VIRTIO_BALLOON_PFN_SHIFT) as u32,
+            ..Default::default()
+        };
 
         Ok(Balloon {
             common: VirtioCommon {
diff --git a/virtio-devices/src/mem.rs b/virtio-devices/src/mem.rs
index 0ec41ffa6..045242a63 100644
--- a/virtio-devices/src/mem.rs
+++ b/virtio-devices/src/mem.rs
@@ -489,12 +489,14 @@ impl MemEpollHandler {
     fn virtio_mem_send_response(
         mem: &GuestMemoryMmap,
         resp_type: u16,
-        resp_state: u16,
+        state: u16,
         status_addr: GuestAddress,
     ) -> u32 {
-        let mut resp = VirtioMemResp::default();
-        resp.resp_type = resp_type;
-        resp.state.state = resp_state;
+        let resp = VirtioMemResp {
+            resp_type,
+            state: VirtioMemRespState { state },
+            ..Default::default()
+        };
         match mem.write_obj(resp, status_addr) {
             Ok(_) => size_of::<VirtioMemResp>() as u32,
             Err(e) => {