vm/vmimpl: add vm.Diagnose method

Diagnose is called on machine hang to try to get
some additional diagnostic information from it.
For now it's all stubs.

1 files changed, 5 insertions, 0 deletions

diff --git a/vm/vmimpl/vmimpl.go b/vm/vmimpl/vmimpl.go
index 532611abd..7d3411ee9 100644
--- a/vm/vmimpl/vmimpl.go
+++ b/vm/vmimpl/vmimpl.go
@@ -43,6 +43,11 @@ type Instance interface {
 	// Command is terminated after timeout. Send on the stop chan can be used to terminate it earlier.
 	Run(timeout time.Duration, stop <-chan bool, command string) (outc <-chan []byte, errc <-chan error, err error)
 
+	// Diagnose forces VM to dump additional debugging info
+	// (e.g. sending some sys-rq's or SIGABORT'ing a Go program).
+	// Returns true if it did anything.
+	Diagnose() bool
+
 	// Close stops and destroys the VM.
 	Close()
 }