Make sure run_vcpu does not create spans

Signed-off-by: Ludvig Liljenberg <[email protected]>

Author: ludfjig

src/hyperlight_host/src/hypervisor/hyperv_linux.rs

@@ -559,7 +559,7 @@ impl Hypervisor for HypervLinuxDriver {
         )
     }
 
-    #[instrument(err(Debug), skip_all, parent = Span::current(), level = "Trace")]
+    // Note, this function should not be instrumented with a span as it is called after setting up guest trace span
     fn run_vcpu(&mut self) -> Result<VmExit> {
         const HALT: hv_message_type = hv_message_type_HVMSG_X64_HALT;
         const IO_PORT: hv_message_type = hv_message_type_HVMSG_X64_IO_PORT_INTERCEPT;

src/hyperlight_host/src/hypervisor/hyperv_windows.rs

@@ -474,6 +474,7 @@ impl Hypervisor for HypervWindowsDriver {
         )
     }
 
+    // Note, this function should not be instrumented with a span as it is called after setting up guest trace span
     #[expect(non_upper_case_globals, reason = "Windows API constant are lower case")]
     fn run_vcpu(&mut self) -> Result<VmExit> {
         let mut exit_context: WHV_RUN_VP_EXIT_CONTEXT = Default::default();

src/hyperlight_host/src/hypervisor/kvm.rs

@@ -548,7 +548,7 @@ impl Hypervisor for KVMDriver {
         )
     }
 
-    #[instrument(err(Debug), skip_all, parent = Span::current(), level = "Trace")]
+    // Note, this function should not be instrumented with a span as it is called after setting up guest trace span
     fn run_vcpu(&mut self) -> Result<VmExit> {
         match self.vcpu_fd.run() {
             Ok(VcpuExit::Hlt) => Ok(VmExit::Halt()),

src/hyperlight_host/src/hypervisor/mod.rs

@@ -223,7 +223,7 @@ pub(crate) trait Hypervisor: Debug + Send {
                     //    - Signals will interrupt the guest (RUNNING_BIT=true), causing VmExit::Cancelled()
                     //    - If the guest completes before any signals arrive, kill() may have no effect
                     //      - If there are more iterations to do (IO/host func, etc.), the next iteration will be cancelled
-                    let exit_reason = self.run_vcpu();
+                    let exit_reason = self.run_vcpu(); // Note, this function must not create any spans as it is called after setting up guest trace span
 
                     // End current host trace by closing the current span that captures traces
                     // happening when a guest exits and re-enters.