xend: Fix check for request to detach non-existent device

This fixes the check for a request to detatch a non-existent device
in pci_device_configure. The previous check was bogus because the
format of AUTO_PHP_SLOT_STR is not the same as that of x['vslot'].

However, it works in a slightly non-obvious way, checking that vslot
hasn't been altered from its initial value AUTO_PHP_SLOT_STR. To
make this shceme a little clearer, use an empty string as the inital
value.

Formting issues asside, neither AUTO_PHP_SLOT_STR nor the empty
string are valid values for x['vslot']. In the event
of invalid data (indicating a bug), it should be caught by
self.hvm_destroyPCIDevice.

Signed-off-by: Simon Horman <horms@verge.net.au>

diff --git a/tools/python/xen/xend/XendDomainInfo.py b/tools/python/xen/xend/XendDomainInfo.py
index 6922191350bff450e1db57f02dd3fe1a5cfdfd2c..2c75c91fcf2f59415ba32185f053e0c6036542f5 100644 (file)
--- a/tools/python/xen/xend/XendDomainInfo.py
+++ b/tools/python/xen/xend/XendDomainInfo.py
@@ -854,7 +854,7 @@ class XendDomainInfo:
                 existing_dev_uuid = sxp.child_value(existing_dev_info, 'uuid')
                 existing_pci_conf = self.info['devices'][existing_dev_uuid][1]
                 existing_pci_devs = existing_pci_conf['devs']
-                vslot = AUTO_PHP_SLOT_STR
+                vslot = ""
                 for x in existing_pci_devs:
                     if ( int(x['domain'], 16) == int(dev['domain'], 16) and
                          int(x['bus'], 16) == int(dev['bus'], 16) and
@@ -862,7 +862,7 @@ class XendDomainInfo:
                          int(x['func'], 16) == int(dev['func'], 16) ):
                         vslot = assigned_or_requested_vslot(x)
                         break
-                if vslot == AUTO_PHP_SLOT_STR:
+                if vslot == "":
                     raise VmError("Device %04x:%02x:%02x.%01x is not connected"
                                   % (int(dev['domain'],16), int(dev['bus'],16),
                                      int(dev['slot'],16), int(dev['func'],16)))