fix(vmm): call KVMCLOCK_CTRL when pausing

This is to avoid guest kernel panic on resume path
due to softlockup detection.

Signed-off-by: Nikita Kalyazin <[email protected]>

src/vmm/src/vstate/vcpu/mod.rs

@@ -296,8 +296,11 @@ impl Vcpu {
                     .send(VcpuResponse::Paused)
                     .expect("vcpu channel unexpectedly closed");
 
-                // TODO: we should call `KVM_KVMCLOCK_CTRL` here to make sure
-                // TODO continued: the guest soft lockup watchdog does not panic on Resume.
+                // Calling `KVM_KVMCLOCK_CTRL` to make sure the guest softlockup watchdog
+                // does not panic on resume, see https://docs.kernel.org/virt/kvm/api.html .
+                // Unwrapping to exit immediately if we fail to do that.
+                #[cfg(target_arch = "x86_64")]
+                self.kvm_vcpu.fd.kvmclock_ctrl().unwrap();
 
                 // Move to 'paused' state.
                 state = StateMachine::next(Self::paused);