libvirt/7a1452f5-libxl-empty-cdrom.patch

commit 7a1452f5334f98680187ae6d11fe2a49c1b38548
Author: Stefan Bader <stefan.bader@canonical.com>
Date:   Thu Mar 27 17:55:03 2014 +0100

    libxl: Set disk format for empty cdrom device
    
    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@canonical.com>

Index: libvirt-1.2.3/src/libxl/libxl_conf.c
===================================================================
--- libvirt-1.2.3.orig/src/libxl/libxl_conf.c
+++ libvirt-1.2.3/src/libxl/libxl_conf.c
@@ -827,6 +827,9 @@ libxlMakeDisk(virDomainDiskDefPtr l_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"));