libxl: fix vfb related assertion problem when starting pv-domU

When a config-file for a pv-domU has a vfb section with a vnc=0
option then a "xl create" for that domU crashes with the message

xl: libxl.c:252: libxl_defbool_val: Assertion `!libxl_defbool_is_default(db)'
failed.

and the domU hangs early in the start.

This patch fixes the cause of the assertion and let the domU start
normally.

This problem exists since xen 4.2.

Signed-off-by: Ronny Hegewald <Ronny.Hegewald@online.de>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>

diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index be457f47653f15b999ae4d6402c09fe90d1f1eea..acb240a1a38bf41685e52bb29677ce9ce0e07ec9 100644 (file)
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -3186,6 +3186,8 @@ int libxl__device_vfb_setdefault(libxl__gc *gc, libxl_device_vfb *vfb)
         }
 
         libxl_defbool_setdefault(&vfb->vnc.findunused, true);
+    } else {
+        libxl_defbool_setdefault(&vfb->vnc.findunused, false);
     }
 
     libxl_defbool_setdefault(&vfb->sdl.enable, false);