[Xen-devel] [PATCH] hotplug: ignore xenstore-read error

[Kouya Shimura <kouya@xxxxxxxxxxxxxx>]

A guest occasionally fails to reboot. xend.log shows:

[2010-02-16 09:52:46 5413] ERROR (XendDomainInfo:2061) Failed to restart domain 
82.
Traceback (most recent call last):
  File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line 
2047, in _restart
    new_dom.waitForDevices()
  File "usr/lib64/python2.4/site-packages/xen/xend/XendDomainInfo.py", line 
1068, in waitForDevices
    self.getDeviceController(devclass).waitForDevices()
  File "usr/lib64/python2.4/site-packages/xen/xend/server/DevController.py", 
line 140, in waitForDevices
    return map(self.waitForDevice, self.deviceIDs())
  File "usr/lib64/python2.4/site-packages/xen/xend/server/DevController.py", 
line 164, in waitForDevice
    raise VmError("Device %s (%s) could not be connected. "
VmError: Device 51712 (tap) could not be connected. xenstore-read 
backend/tap/82/51712/params failed.


The failure to read "backend/tap/<domid>/*" in the xenstore is a usual
case since the domain is gone after xenstore-ls command is executed.
The error should be ignored.

This patch should be applied to xen-3.4 too.

Signed-off-by: Kouya Shimura <kouya@xxxxxxxxxxxxxx>

diff -r 3a0bd7ca6b11 tools/hotplug/Linux/blktap
--- a/tools/hotplug/Linux/blktap        Mon Feb 15 17:54:04 2010 +0000
+++ b/tools/hotplug/Linux/blktap        Tue Feb 16 15:33:58 2010 +0900
@@ -23,7 +23,7 @@ check_blktap_sharing()
     do
         for dev in $(xenstore-list "$base_path/$dom")
         do
-            params=$(xenstore_read "$base_path/$dom/$dev/params" | cut -d: -f2)
+            params=$(xenstore_read_default "$base_path/$dom/$dev/params" "" | 
cut -d: -f2)
             if [ "$file" = "$params" ]
             then
 
@@ -35,7 +35,7 @@ check_blktap_sharing()
                         return
                     fi
                 else 
-                    local m=$(xenstore_read "$base_path/$dom/$dev/mode")
+                    local m=$(xenstore_read_default 
"$base_path/$dom/$dev/mode" "")
                     m=$(canonicalise_mode "$m")
 
                     if [ "$m" = 'w' ] 
diff -r 3a0bd7ca6b11 tools/hotplug/Linux/block
--- a/tools/hotplug/Linux/block Mon Feb 15 17:54:04 2010 +0000
+++ b/tools/hotplug/Linux/block Tue Feb 16 15:33:58 2010 +0900
@@ -100,7 +100,7 @@ check_sharing()
             return
           fi
         else
-          local m=$(xenstore_read "$base_path/$dom/$dev/mode")
+          local m=$(xenstore_read_default "$base_path/$dom/$dev/mode" "")
           m=$(canonicalise_mode "$m")
 
           if [ "$m" = 'w' ]

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel