[Patch v3] x86/time: Update wallclock in shared info when altering domain time offset

[Andrew Cooper <andrew.cooper3@citrix.com>]

domain_set_time_offset() udpates d->time_offset_seconds, but does not correct
the wallclock in the shared info, meaning that it is incorrect until the next
XENPF_settime hypercall from dom0 which resynchronises the wallclock for all
domains.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
CC: Keir Fraser <keir@xen.org>
CC: Jan Beulich <JBeulich@suse.com>
CC: Paul Durrant <Paul.Durrant@citrix.com>
---
This should be backported to all stable releases.

Changes since v2:
 * No real need to write the wallclock at shinfo-create time.  Given f8e8fd56,
   it will be correct before an HVM PV aware domain can actually get at it,
   and this avoids use of a global lock (even though the use is brief).

Changes since v1:
 * s/watchdog/wallclock/ - Stupid typo.
---
 xen/arch/x86/time.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c
index cf8bc78..f047cb3 100644
--- a/xen/arch/x86/time.c
+++ b/xen/arch/x86/time.c
@@ -931,6 +931,7 @@ void domain_set_time_offset(struct domain *d, int32_t time_offset_seconds)
     d->time_offset_seconds = time_offset_seconds;
     if ( is_hvm_domain(d) )
         rtc_update_clock(d);
+    update_domain_wallclock_time(d);
 }
 
 int cpu_frequency_change(u64 freq)
-- 
1.7.10.4