[Qemu-devel] [PATCH 3/6] xen: Skip backend initialization for stubdom

[Jason Andryuk <jandryuk@gmail.com>]

When QEMU is running in a stubdom, it does not provide any
Paravirtualized backends.  Those still run in dom0 or another driver
domain.  Therefore we skip backend initialization (xen_bus_init and
xen_be_init) for the stubdom case.

Original patch by Anthony PERARD <anthony.perard@citrix.com>

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
---
 hw/i386/xen/xen-hvm.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/hw/i386/xen/xen-hvm.c b/hw/i386/xen/xen-hvm.c
index c20c4b27f6..4b62f070cb 100644
--- a/hw/i386/xen/xen-hvm.c
+++ b/hw/i386/xen/xen-hvm.c
@@ -1485,8 +1485,6 @@ void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
     QLIST_INIT(&state->dev_list);
     device_listener_register(&state->device_listener);
 
-    xen_bus_init();
-
     xenstore = xs_open(0);
     if (!xenstore) {
         error_report("Can't connect to xenstored");
@@ -1495,12 +1493,16 @@ void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
 
     qemu_set_fd_handler(xs_fileno(xenstore), xenstore_update, NULL, NULL);
 
-    /* Initialize backend core & drivers */
-    if (xen_be_init() != 0) {
-        error_report("xen backend core setup failed");
-        goto err;
+    if (!xen_stubdom_enabled()) {
+        xen_bus_init();
+
+        /* Initialize backend core & drivers */
+        if (xen_be_init() != 0) {
+            error_report("xen backend core setup failed");
+            goto err;
+        }
+        xen_be_register_common();
     }
-    xen_be_register_common();
 
     QLIST_INIT(&xen_physmap);
     xen_read_physmap(state);
-- 
2.20.1