tools/hotplug: systemd: Don't ever kill xenstored

Don't kill xenstored as part of the usual service shutdown process to
prevent hangs on shutdown where the kernel tries to unplug a VIF
after xenstored has exited.

In an ideal case with all guests cooperating, xendomains will have shut
down all guests before xenstored is killed.

However in the uncooperative case, malicious or crashed guests may still
be running after xendomains has exited and this should not block the
shutdown/reboot of dom0.

Xenstored has no state to sync to disk, and never used to be killed in
the sysvinit case; observe the warning in xencommons.  Our testing has
shown regressions caused by the change in behaviour between sysvinit and
systemd when it comes to killing xenstored.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
[ ijc -- added systemd to title ]
(cherry picked from commit 96e0ee8386cf690c28c46a2c9f75cd2b03f646e1)

diff --git a/tools/hotplug/Linux/systemd/xenstored.service.in b/tools/hotplug/Linux/systemd/xenstored.service.in
index 0f0ac58db2cb25a40a015038b335cbedff9a40e6..a5f836b5eb5119daf5cce6dfe2f7bd27854f0491 100644 (file)
--- a/tools/hotplug/Linux/systemd/xenstored.service.in
+++ b/tools/hotplug/Linux/systemd/xenstored.service.in
@@ -8,6 +8,7 @@ ConditionPathExists=/proc/xen/capabilities
 
 [Service]
 Type=notify
+KillMode=none
 Environment=XENSTORED_ARGS=
 Environment=XENSTORED=@XENSTORED@
 EnvironmentFile=-@CONFIG_DIR@/@CONFIG_LEAF_DIR@/xencommons