Merge branch 'linus' into x86/urgent

Required to queue a dependent fix.

1 files changed, 24 insertions, 9 deletions

diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index 2a8571f72b17..4ca2fd46645d 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -76,6 +76,19 @@ static inline void irq_chip_write_msi_msg(struct irq_data *data,
 	data->chip->irq_write_msi_msg(data, msg);
 }
 
+static void msi_check_level(struct irq_domain *domain, struct msi_msg *msg)
+{
+	struct msi_domain_info *info = domain->host_data;
+
+	/*
+	 * If the MSI provider has messed with the second message and
+	 * not advertized that it is level-capable, signal the breakage.
+	 */
+	WARN_ON(!((info->flags & MSI_FLAG_LEVEL_CAPABLE) &&
+		  (info->chip->flags & IRQCHIP_SUPPORTS_LEVEL_MSI)) &&
+		(msg[1].address_lo || msg[1].address_hi || msg[1].data));
+}
+
 /**
  * msi_domain_set_affinity - Generic affinity setter function for MSI domains
  * @irq_data:	The irq data associated to the interrupt
@@ -89,13 +102,14 @@ int msi_domain_set_affinity(struct irq_data *irq_data,
 			    const struct cpumask *mask, bool force)
 {
 	struct irq_data *parent = irq_data->parent_data;
-	struct msi_msg msg;
+	struct msi_msg msg[2] = { [1] = { }, };
 	int ret;
 
 	ret = parent->chip->irq_set_affinity(parent, mask, force);
 	if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE) {
-		BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg));
-		irq_chip_write_msi_msg(irq_data, &msg);
+		BUG_ON(irq_chip_compose_msi_msg(irq_data, msg));
+		msi_check_level(irq_data->domain, msg);
+		irq_chip_write_msi_msg(irq_data, msg);
 	}
 
 	return ret;
@@ -104,20 +118,21 @@ int msi_domain_set_affinity(struct irq_data *irq_data,
 static int msi_domain_activate(struct irq_domain *domain,
 			       struct irq_data *irq_data, bool early)
 {
-	struct msi_msg msg;
+	struct msi_msg msg[2] = { [1] = { }, };
 
-	BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg));
-	irq_chip_write_msi_msg(irq_data, &msg);
+	BUG_ON(irq_chip_compose_msi_msg(irq_data, msg));
+	msi_check_level(irq_data->domain, msg);
+	irq_chip_write_msi_msg(irq_data, msg);
 	return 0;
 }
 
 static void msi_domain_deactivate(struct irq_domain *domain,
 				  struct irq_data *irq_data)
 {
-	struct msi_msg msg;
+	struct msi_msg msg[2];
 
-	memset(&msg, 0, sizeof(msg));
-	irq_chip_write_msi_msg(irq_data, &msg);
+	memset(msg, 0, sizeof(msg));
+	irq_chip_write_msi_msg(irq_data, msg);
 }
 
 static int msi_domain_alloc(struct irq_domain *domain, unsigned int virq,