From 860939d677b956927c4265ece7cf19127323ee06 Mon Sep 17 00:00:00 2001
From: Muminul Islam <muislam@microsoft.com>
Date: Wed, 1 May 2024 15:19:41 -0700
Subject: [PATCH] vmm: pause/resume VM during the VM events

For MSHV we always create frozen partition, so we
resume the VM during boot. Also during pause and resume
VM events we call hypervisor specific API.

Signed-off-by: Muminul Islam <muislam@microsoft.com>
---
 vmm/src/vm.rs | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/vmm/src/vm.rs b/vmm/src/vm.rs
index 559d51388..6c183f807 100644
--- a/vmm/src/vm.rs
+++ b/vmm/src/vm.rs
@@ -319,6 +319,9 @@ pub enum Error {
 
     #[error("Error injecting NMI")]
     ErrorNmi,
+
+    #[error("Error resuming the VM: {0}")]
+    ResumeVm(#[source] hypervisor::HypervisorVmError),
 }
 pub type Result<T> = result::Result<T, Error>;
 
@@ -2173,6 +2176,11 @@ impl Vm {
             self.vm.tdx_finalize().map_err(Error::FinalizeTdx)?;
         }
 
+        // Resume the vm for MSHV
+        if current_state == VmState::Created {
+            self.vm.resume().map_err(Error::ResumeVm)?;
+        }
+
         self.cpu_manager
             .lock()
             .unwrap()
@@ -2487,6 +2495,10 @@ impl Pausable for Vm {
         self.cpu_manager.lock().unwrap().pause()?;
         self.device_manager.lock().unwrap().pause()?;
 
+        self.vm
+            .pause()
+            .map_err(|e| MigratableError::Pause(anyhow!("Could not pause the VM: {}", e)))?;
+
         *state = new_state;
 
         event!("vm", "paused");
@@ -2495,6 +2507,7 @@ impl Pausable for Vm {
 
     fn resume(&mut self) -> std::result::Result<(), MigratableError> {
         event!("vm", "resuming");
+        let current_state = self.get_state().unwrap();
         let mut state = self
             .state
             .try_write()
@@ -2514,6 +2527,13 @@ impl Pausable for Vm {
                 })?;
             }
         }
+
+        if current_state == VmState::Paused {
+            self.vm
+                .resume()
+                .map_err(|e| MigratableError::Resume(anyhow!("Could not resume the VM: {}", e)))?;
+        }
+
         self.device_manager.lock().unwrap().resume()?;
 
         // And we're back to the Running state.