The XML config for a CDROM device can be without a source path,
indicating that there is no media present. Without this change
the libxl driver fails to start a guest in that case because
the libxl library checks for the LIBXL_DISK_FORMAT_EMPTY format
type and tries to stat the NULL pointer that gets passed on.
libxl: error: libxl_device.c:265:libxl__device_disk_set_backend:
Disk vdev=hdc failed to stat: (null): Bad address
Signed-off-by: Stefan Bader <stefan.bader(a)canonical.com>
---
src/libxl/libxl_conf.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c
index de6f7ce..b8de72a 100644
--- a/src/libxl/libxl_conf.c
+++ b/src/libxl/libxl_conf.c
@@ -827,6 +827,9 @@ libxlMakeDisk(virDomainDiskDefPtr l_disk, libxl_device_disk *x_disk)
x_disk->removable = 1;
x_disk->readwrite = !l_disk->readonly;
x_disk->is_cdrom = l_disk->device == VIR_DOMAIN_DISK_DEVICE_CDROM ? 1 : 0;
+ /* An empty CDROM must have the empty format, otherwise libxl fails. */
+ if (x_disk->is_cdrom && !x_disk->pdev_path)
+ x_disk->format = LIBXL_DISK_FORMAT_EMPTY;
if (l_disk->transient) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("libxenlight does not support transient disks"));
--
1.7.9.5