1 files changed, 34 insertions, 14 deletions

diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index eaba42a89c8f..679b2cbd2de4 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -433,15 +433,20 @@ static bool pirq_needs_eoi_flag(unsigned irq)
 	return info->u.pirq.flags & PIRQ_NEEDS_EOI;
 }
 
-static void bind_evtchn_to_cpu(evtchn_port_t evtchn, unsigned int cpu)
+static void bind_evtchn_to_cpu(evtchn_port_t evtchn, unsigned int cpu,
+			       bool force_affinity)
 {
 	int irq = get_evtchn_to_irq(evtchn);
 	struct irq_info *info = info_for_irq(irq);
 
 	BUG_ON(irq == -1);
-#ifdef CONFIG_SMP
-	cpumask_copy(irq_get_affinity_mask(irq), cpumask_of(cpu));
-#endif
+
+	if (IS_ENABLED(CONFIG_SMP) && force_affinity) {
+		cpumask_copy(irq_get_affinity_mask(irq), cpumask_of(cpu));
+		cpumask_copy(irq_get_effective_affinity_mask(irq),
+			     cpumask_of(cpu));
+	}
+
 	xen_evtchn_port_bind_to_cpu(evtchn, cpu, info->cpu);
 
 	info->cpu = cpu;
@@ -788,7 +793,7 @@ static unsigned int __startup_pirq(unsigned int irq)
 		goto err;
 
 	info->evtchn = evtchn;
-	bind_evtchn_to_cpu(evtchn, 0);
+	bind_evtchn_to_cpu(evtchn, 0, false);
 
 	rc = xen_evtchn_port_setup(evtchn);
 	if (rc)
@@ -1107,8 +1112,14 @@ static int bind_evtchn_to_irq_chip(evtchn_port_t evtchn, struct irq_chip *chip)
 			irq = ret;
 			goto out;
 		}
-		/* New interdomain events are bound to VCPU 0. */
-		bind_evtchn_to_cpu(evtchn, 0);
+		/*
+		 * New interdomain events are initially bound to vCPU0 This
+		 * is required to setup the event channel in the first
+		 * place and also important for UP guests because the
+		 * affinity setting is not invoked on them so nothing would
+		 * bind the channel.
+		 */
+		bind_evtchn_to_cpu(evtchn, 0, false);
 	} else {
 		struct irq_info *info = info_for_irq(irq);
 		WARN_ON(info == NULL || info->type != IRQT_EVTCHN);
@@ -1156,7 +1167,11 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
 			irq = ret;
 			goto out;
 		}
-		bind_evtchn_to_cpu(evtchn, cpu);
+		/*
+		 * Force the affinity mask to the target CPU so proc shows
+		 * the correct target.
+		 */
+		bind_evtchn_to_cpu(evtchn, cpu, true);
 	} else {
 		struct irq_info *info = info_for_irq(irq);
 		WARN_ON(info == NULL || info->type != IRQT_IPI);
@@ -1269,7 +1284,11 @@ int bind_virq_to_irq(unsigned int virq, unsigned int cpu, bool percpu)
 			goto out;
 		}
 
-		bind_evtchn_to_cpu(evtchn, cpu);
+		/*
+		 * Force the affinity mask for percpu interrupts so proc
+		 * shows the correct target.
+		 */
+		bind_evtchn_to_cpu(evtchn, cpu, percpu);
 	} else {
 		struct irq_info *info = info_for_irq(irq);
 		WARN_ON(info == NULL || info->type != IRQT_VIRQ);
@@ -1634,8 +1653,7 @@ void rebind_evtchn_irq(evtchn_port_t evtchn, int irq)
 
 	mutex_unlock(&irq_mapping_update_lock);
 
-        bind_evtchn_to_cpu(evtchn, info->cpu);
-	irq_set_affinity(irq, cpumask_of(info->cpu));
+	bind_evtchn_to_cpu(evtchn, info->cpu, false);
 
 	/* Unmask the event channel. */
 	enable_irq(irq);
@@ -1669,7 +1687,7 @@ static int xen_rebind_evtchn_to_cpu(evtchn_port_t evtchn, unsigned int tcpu)
 	 * it, but don't do the xenlinux-level rebind in that case.
 	 */
 	if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0)
-		bind_evtchn_to_cpu(evtchn, tcpu);
+		bind_evtchn_to_cpu(evtchn, tcpu, false);
 
 	if (!masked)
 		unmask_evtchn(evtchn);
@@ -1798,7 +1816,8 @@ static void restore_cpu_virqs(unsigned int cpu)
 
 		/* Record the new mapping. */
 		(void)xen_irq_info_virq_setup(cpu, irq, evtchn, virq);
-		bind_evtchn_to_cpu(evtchn, cpu);
+		/* The affinity mask is still valid */
+		bind_evtchn_to_cpu(evtchn, cpu, false);
 	}
 }
 
@@ -1823,7 +1842,8 @@ static void restore_cpu_ipis(unsigned int cpu)
 
 		/* Record the new mapping. */
 		(void)xen_irq_info_ipi_setup(cpu, irq, evtchn, ipi);
-		bind_evtchn_to_cpu(evtchn, cpu);
+		/* The affinity mask is still valid */
+		bind_evtchn_to_cpu(evtchn, cpu, false);
 	}
 }