x86: Fixes for S3 suspend resume:

 - Fix wallclock resume by remembering the offset from CMOS time to
   UTC time
 - Restore dom0's CPU affinity (lost during
   continue_hypercall_on_cpu())

Signed-off-by: Xu Dongxiao <dongxiao.xu@intel.com>

2 files changed, 9 insertions, 1 deletions

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 588a7fb1f7..957e33ef57 100644
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -1420,6 +1420,7 @@ static void continue_hypercall_on_cpu_helper(struct vcpu *v)
     regs->eax = info->func(info->data);
 
     v->arch.schedule_tail = info->saved_schedule_tail;
+    v->cpu_affinity = info->saved_affinity;
     v->arch.continue_info = NULL;
 
     xfree(info);
diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c
index a9e2b5b735..6d4946245b 100644
--- a/xen/arch/x86/time.c
+++ b/xen/arch/x86/time.c
@@ -971,8 +971,14 @@ unsigned long get_localtime(struct domain *d)
         + d->time_offset_seconds;
 }
 
+/* "cmos_utc_offset" is the difference between UTC time and CMOS time. */
+static long cmos_utc_offset; /* in seconds */
+
 int time_suspend(void)
 {
+    cmos_utc_offset = (wc_sec + (wc_nsec + NOW()) / 1000000000ULL)
+        - get_cmos_time();
+
     /* Better to cancel calibration timer for accuracy. */
     kill_timer(&this_cpu(cpu_time).calibration_timer);
 
@@ -986,7 +992,8 @@ int time_resume(void)
     set_time_scale(&this_cpu(cpu_time).tsc_scale, tmp);
 
     resume_platform_timer();
-    do_settime(get_cmos_time(), 0, read_platform_stime());
+
+    do_settime(get_cmos_time() + cmos_utc_offset, 0, read_platform_stime());
 
     init_percpu_time();