3 files changed, 27 insertions, 17 deletions

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 9f808af..e11efbd 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -129,6 +129,21 @@ static void xen_vcpu_setup(int cpu)
 
 	BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
 
+	/*
+	 * This path is called twice on PVHVM - first during bootup via
+	 * smp_init -> xen_hvm_cpu_notify, and then if the VCPU is being
+	 * hotplugged: cpu_up -> xen_hvm_cpu_notify.
+	 * As we can only do the VCPUOP_register_vcpu_info once lets
+	 * not over-write its result.
+	 *
+	 * For PV it is called during restore (xen_vcpu_restore) and bootup
+	 * (xen_setup_vcpu_info_placement). The hotplug mechanism does not
+	 * use this function.
+	 */
+	if (xen_hvm_domain()) {
+		if (per_cpu(xen_vcpu, cpu) == &per_cpu(xen_vcpu_info, cpu))
+			return;
+	}
 	if (cpu < MAX_VIRT_CPUS)
 		per_cpu(xen_vcpu,cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
 
@@ -1365,8 +1380,11 @@ static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self,
 	switch (action) {
 	case CPU_UP_PREPARE:
 		xen_vcpu_setup(cpu);
-		if (xen_have_vector_callback)
+		if (xen_have_vector_callback) {
 			xen_init_lock_cpu(cpu);
+			if (xen_feature(XENFEAT_hvm_safe_pvclock))
+				xen_setup_timer(cpu);
+		}
 		break;
 	default:
 		break;
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index d957dce..a0aed70 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -2011,6 +2011,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
 	.lazy_mode = {
 		.enter = paravirt_enter_lazy_mmu,
 		.leave = xen_leave_lazy_mmu,
+		.flush = paravirt_flush_lazy_mmu,
 	},
 
 	.set_fixmap = xen_set_fixmap,
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 5158c50..19568a0 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -36,9 +36,8 @@ static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate);
 /* snapshots of runstate info */
 static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate_snapshot);
 
-/* unused ns of stolen and blocked time */
+/* unused ns of stolen time */
 static DEFINE_PER_CPU(u64, xen_residual_stolen);
-static DEFINE_PER_CPU(u64, xen_residual_blocked);
 
 /* return an consistent snapshot of 64-bit time/counter value */
 static u64 get64(const u64 *p)
@@ -115,7 +114,7 @@ static void do_stolen_accounting(void)
 {
 	struct vcpu_runstate_info state;
 	struct vcpu_runstate_info *snap;
-	s64 blocked, runnable, offline, stolen;
+	s64 runnable, offline, stolen;
 	cputime_t ticks;
 
 	get_runstate_snapshot(&state);
@@ -125,7 +124,6 @@ static void do_stolen_accounting(void)
 	snap = &__get_cpu_var(xen_runstate_snapshot);
 
 	/* work out how much time the VCPU has not been runn*ing*  */
-	blocked = state.time[RUNSTATE_blocked] - snap->time[RUNSTATE_blocked];
 	runnable = state.time[RUNSTATE_runnable] - snap->time[RUNSTATE_runnable];
 	offline = state.time[RUNSTATE_offline] - snap->time[RUNSTATE_offline];
 
@@ -141,17 +139,6 @@ static void do_stolen_accounting(void)
 	ticks = iter_div_u64_rem(stolen, NS_PER_TICK, &stolen);
 	__this_cpu_write(xen_residual_stolen, stolen);
 	account_steal_ticks(ticks);
-
-	/* Add the appropriate number of ticks of blocked time,
-	   including any left-overs from last time. */
-	blocked += __this_cpu_read(xen_residual_blocked);
-
-	if (blocked < 0)
-		blocked = 0;
-
-	ticks = iter_div_u64_rem(blocked, NS_PER_TICK, &blocked);
-	__this_cpu_write(xen_residual_blocked, blocked);
-	account_idle_ticks(ticks);
 }
 
 /* Get the TSC speed from Xen */
@@ -482,7 +469,11 @@ static void xen_hvm_setup_cpu_clockevents(void)
 {
 	int cpu = smp_processor_id();
 	xen_setup_runstate_info(cpu);
-	xen_setup_timer(cpu);
+	/*
+	 * xen_setup_timer(cpu) - snprintf is bad in atomic context. Hence
+	 * doing it xen_hvm_cpu_notify (which gets called by smp_init during
+	 * early bootup and also during CPU hotplug events).
+	 */
 	xen_setup_cpu_clockevents();
 }