tools/libxl: check QEMU state before resume dm

check QEMU state before resume dm on QEMU_XEN_TRADITIONAL.

Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com>
CC: Ian Campbell <Ian.Campbell@citrix.com>
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>

diff --git a/tools/libxl/libxl_dom_suspend.c b/tools/libxl/libxl_dom_suspend.c
index a90800dfbf135069dc6472f8cd3bda2cf84d66b0..4cc01ad0facc65ded31231a71adcc9f605d2d9f2 100644 (file)
--- a/tools/libxl/libxl_dom_suspend.c
+++ b/tools/libxl/libxl_dom_suspend.c
@@ -375,11 +375,19 @@ static void domain_suspend_callback_common_done(libxl__egc *egc,
 
 int libxl__domain_resume_device_model(libxl__gc *gc, uint32_t domid)
 {
+    const char *path, *state;
 
     switch (libxl__device_model_version_running(gc, domid)) {
     case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL: {
-        libxl__qemu_traditional_cmd(gc, domid, "continue");
-        libxl__wait_for_device_model_deprecated(gc, domid, "running", NULL, NULL, NULL);
+        uint32_t dm_domid = libxl_get_stubdom_id(CTX, domid);
+
+        path = libxl__device_model_xs_path(gc, dm_domid, domid, "/state");
+        state = libxl__xs_read(gc, XBT_NULL, path);
+        if (state != NULL && !strcmp(state, "paused")) {
+            libxl__qemu_traditional_cmd(gc, domid, "continue");
+            libxl__wait_for_device_model_deprecated(gc, domid, "running",
+                                                    NULL, NULL, NULL);
+        }
         break;
     }
     case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN: