2 files changed, 22 insertions, 1 deletions

diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
index d1c217b23a42..bce15cf4a8df 100644
--- a/drivers/xen/xenbus/xenbus_xs.c
+++ b/drivers/xen/xenbus/xenbus_xs.c
@@ -618,6 +618,23 @@ static struct xenbus_watch *find_watch(const char *token)
         return NULL;
 }
 
+static void xs_reset_watches(void)
+{
+        int err, supported = 0;
+
+        if (!xen_hvm_domain())
+                return;
+
+        err = xenbus_scanf(XBT_NIL, "control",
+                        "platform-feature-xs_reset_watches", "%d", &supported);
+        if (err != 1 || !supported)
+                return;
+
+        err = xs_error(xs_single(XBT_NIL, XS_RESET_WATCHES, "", NULL));
+        if (err && err != -EEXIST)
+                printk(KERN_WARNING "xs_reset_watches failed: %d\n", err);
+}
+
 /* Register callback to watch this node. */
 int register_xenbus_watch(struct xenbus_watch *watch)
 {
@@ -900,5 +917,8 @@ int xs_init(void)
         if (IS_ERR(task))
                 return PTR_ERR(task);
 
+        /* shutdown watches for kexec boot */
+        xs_reset_watches();
+
         return 0;
 }
diff --git a/include/xen/interface/io/xs_wire.h b/include/xen/interface/io/xs_wire.h
index 7cdfca24eafb..794deb07eb53 100644
--- a/include/xen/interface/io/xs_wire.h
+++ b/include/xen/interface/io/xs_wire.h
@@ -29,7 +29,8 @@ enum xsd_sockmsg_type
     XS_IS_DOMAIN_INTRODUCED,
     XS_RESUME,
     XS_SET_TARGET,
-    XS_RESTRICT
+    XS_RESTRICT,
+    XS_RESET_WATCHES,
 };
 
 #define XS_WRITE_NONE "NONE"