Origin: https://bugs.launchpad.net/qemu/+bug/1217339/comments/2
Origin: https://lists.nongnu.org/archive/html/qemu-devel/2017-03/msg03039.html

diff --git a/softmmu/vl.c b/softmmu/vl.c
index 1ad1c04637..9e07fe1dbb 100644
--- a/softmmu/vl.c
+++ b/softmmu/vl.c
@@ -1898,7 +1898,11 @@ void qemu_system_killed(int signal, pid_t pid)
     /* Cannot call qemu_system_shutdown_request directly because
      * we are in a signal handler.
      */
-    shutdown_requested = SHUTDOWN_CAUSE_HOST_SIGNAL;
+    if (signal == SIGHUP) {
+        powerdown_requested = 1;
+    } else {
+        shutdown_requested = SHUTDOWN_CAUSE_HOST_SIGNAL;
+    }
     qemu_notify_event();
 }