Run timesyncd in virtual machines

Patch backported from upstream git.

Closes: #762343

debian/changelog

@@ -6,6 +6,7 @@ systemd (215-15) UNRELEASED; urgency=medium
 
   [ Martin Pitt ]
   * Fix getty restart loop when PTS device is gone. (Closes: #780711)
+  * Run timesyncd in virtual machines. (Closes: #762343)
 
  -- Martin Pitt <mpitt@debian.org>  Wed, 08 Apr 2015 10:53:38 +0200
 

debian/patches/series

@@ -145,6 +145,7 @@ journald-also-increase-the-SendBuffer-of-dev-log-to-.patch
 list-add-macro-for-iterating-through-a-list-an-item-.patch
 core-if-two-start-jobs-for-the-same-swap-device-node.patch
 units-make-sure-container-getty-.service-stops-resta.patch
+timesyncd-enable-timesyncd-in-virtual-machines.patch
 
 ## Debian specific patches:
 Add-back-support-for-Debian-specific-config-files.patch

debian/patches/timesyncd-enable-timesyncd-in-virtual-machines.patch

+From: Kay Sievers <kay@vrfy.org>
+Date: Sun, 15 Mar 2015 19:44:59 +0100
+Subject: timesyncd: enable timesyncd in virtual machines
+
+On Fri, Mar 13, 2015 at 8:25 PM, Michael Marineau <michael.marineau@coreos.com> wrote:
+> Currently systemd-timesyncd.service includes
+> ConditionVirtualization=no, disabling it in both containers and
+> virtual machines. Each VM platform tends to deal with or ignore the
+> time problem in their own special ways, KVM/QEMU has the kernel time
+> source kvm-clock, Xen has had different schemes over the years, VMware
+> expects a userspace daemon sync the clock, and other platforms are
+> content to drift with the wind as far as I can tell.
+>
+> I don't know of a robust way to know if a platform needs a little
+> extra help from userspace to keep the clock sane or not but it seems
+> generally safer to try than to risk drifting. Does anyone know of a
+> reason to leave timesyncd off by default? Otherwise switching to
+> ConditionVirtualization=!container should be reasonable.
+---
+ units/systemd-timesyncd.service.in | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/units/systemd-timesyncd.service.in b/units/systemd-timesyncd.service.in
+index 39edafc..8219c95 100644
+--- a/units/systemd-timesyncd.service.in
++++ b/units/systemd-timesyncd.service.in
+@@ -9,7 +9,7 @@
+ Description=Network Time Synchronization
+ Documentation=man:systemd-timesyncd.service(8)
+ ConditionCapability=CAP_SYS_TIME
+-ConditionVirtualization=no
++ConditionVirtualization=!container
+ DefaultDependencies=no
+ RequiresMountsFor=/var/lib/systemd/clock
+ After=systemd-remount-fs.service systemd-tmpfiles-setup.service systemd-sysusers.service