[libvirt] [PATCH] Fix libvirtd restart for domains with PCI passthrough devices

[Chris Lalancette]

When libvirtd shuts down, it places a <state/> tag in the XML
state file it writes out for guests with PCI passthrough
devices.  For devices that are attached at bootup time, the
state tag is empty.  However, at libvirtd startup time, it
ignores anything with a <state/> tag in the XML, effectively
hiding the guest.

I can think of at least 3 ways to fix this:

1)  Don't throw an error on "unknown" tags in
virDomainHostdevSubsysPciDefParseXML().
2)  Have virDomainLoadAllConfigs() pass the
VIR_DOMAIN_XML_INTERNAL_STATUS flag when parsing the domain
XML.
3)  Remove the check for VIR_DOMAIN_XML_INTERNAL_STATUS
when parsing the XML.

I chose approach 3).  My reasoning for this is that the
<state> tag is a legitimate part of the XML, so we should
always offer to parse it.  This fixes the problem with
reconnecting to domains that have PCI passthrough devices.

Signed-off-by: Chris Lalancette <clalance at redhat.com>
---
 src/conf/domain_conf.c |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 74c2337..595c46c 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -2876,7 +2876,7 @@ static int
 virDomainHostdevSubsysPciDefParseXML(virConnectPtr conn,
                                      const xmlNodePtr node,
                                      virDomainHostdevDefPtr def,
-                                     int flags) {
+                                     int flags ATTRIBUTE_UNUSED) {
 
     int ret = -1;
     xmlNodePtr cur;
@@ -2890,8 +2890,7 @@ virDomainHostdevSubsysPciDefParseXML(virConnectPtr conn,
 
                 if (virDomainDevicePCIAddressParseXML(conn, cur, addr) < 0)
                     goto out;
-            } else if ((flags & VIR_DOMAIN_XML_INTERNAL_STATUS) &&
-                       xmlStrEqual(cur->name, BAD_CAST "state")) {
+            } else if (xmlStrEqual(cur->name, BAD_CAST "state")) {
                 /* Legacy back-compat. Don't add any more attributes here */
                 char *devaddr = virXMLPropString(cur, "devaddr");
                 if (devaddr &&
-- 
1.6.6