libxl/netbsd: check num_exec in hotplug function

This basically replicates the same logic in libxl_linux.c but with one
change -- only test num_exec == 0 in nic hotplug case because NetBSD let
QEMU call a script itself. Without this patch libxl will loop
indefinitely trying to execute hotplug script.

Reported-by: John Nemeth <jnemeth@cue.bc.ca>
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>

diff --git a/tools/libxl/libxl_netbsd.c b/tools/libxl/libxl_netbsd.c
index 096c0578fc37e73a8efa9d685c99803d043a7589..a79b8aae2b858e3de0d988846f044db6b1897094 100644 (file)
--- a/tools/libxl/libxl_netbsd.c
+++ b/tools/libxl/libxl_netbsd.c
@@ -68,7 +68,28 @@ int libxl__get_hotplug_script_info(libxl__gc *gc, libxl__device *dev,
 
     switch (dev->backend_kind) {
     case LIBXL__DEVICE_KIND_VBD:
+        if (num_exec != 0) {
+            LOG(DEBUG, "num_exec %d, not running hotplug scripts", num_exec);
+            rc = 0;
+            goto out;
+        }
+        rc = libxl__hotplug(gc, dev, args, action);
+        if (!rc) rc = 1;
+        break;
     case LIBXL__DEVICE_KIND_VIF:
+        /*
+         * If domain has a stubdom we don't have to execute hotplug scripts
+         * for emulated interfaces
+         *
+         * NetBSD let QEMU call a script to plug emulated nic, so
+         * only test if num_exec == 0 in that case.
+         */
+        if ((num_exec != 0) ||
+            (libxl_get_stubdom_id(CTX, dev->domid) && num_exec)) {
+            LOG(DEBUG, "num_exec %d, not running hotplug scripts", num_exec);
+            rc = 0;
+            goto out;
+        }
         rc = libxl__hotplug(gc, dev, args, action);
         if (!rc) rc = 1;
         break;