vmm: Create restored Vm as paused

Thanks to the new way of restoring Vm, we can now create the Vm object
directly with the appropriate VmState rather than having to patch it at
a later time.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

vmm/src/vm.rs

@@ -308,9 +308,6 @@ pub enum Error {
     #[cfg(feature = "guest_debug")]
     #[error("Error coredumping VM: {0:?}")]
     Coredump(GuestDebuggableError),
-
-    #[error("Failed taking the RwLock")]
-    TryRwLock(#[source] anyhow::Error),
 }
 pub type Result<T> = result::Result<T, Error>;
 
@@ -614,6 +611,12 @@ impl Vm {
             None
         };
 
+        let vm_state = if snapshot.is_some() {
+            VmState::Paused
+        } else {
+            VmState::Created
+        };
+
         Ok(Vm {
             #[cfg(feature = "tdx")]
             kernel,
@@ -623,7 +626,7 @@ impl Vm {
             on_tty,
             threads: Vec::with_capacity(1),
             signals: None,
-            state: RwLock::new(VmState::Created),
+            state: RwLock::new(vm_state),
             cpu_manager,
             memory_manager,
             vm,
@@ -2124,10 +2127,6 @@ impl Vm {
     pub fn restore(&mut self) -> Result<()> {
         event!("vm", "restoring");
 
-        let current_state = self.get_state()?;
-        let new_state = VmState::Paused;
-        current_state.valid_transition(new_state)?;
-
         // Now we can start all vCPUs from here.
         self.cpu_manager
             .lock()
@@ -2138,12 +2137,6 @@ impl Vm {
         self.setup_signal_handler()?;
         self.setup_tty()?;
 
-        let mut state = self
-            .state
-            .try_write()
-            .map_err(|e| Error::TryRwLock(anyhow!("Failed taking the lock: {}", e)))?;
-        *state = new_state;
-
         event!("vm", "restored");
         Ok(())
     }