genirq/msi: Handle reactivation only on success

When analyzing the fallout of the x86 vector allocation rework it turned
out that the error handling in msi_domain_alloc_irqs() is broken.

If MSI_FLAG_MUST_REACTIVATE is set for a MSI domain then it clears the
activation flag for a successfully initialized msi descriptor. If a
subsequent initialization fails then the error handling code path does not
deactivate the interrupt because the activation flag got cleared.

Move the clearing of the activation flag outside of the initialization loop
so that an eventual failure can be cleaned up correctly.

Fixes: 22d0b12f3560 ("genirq/irqdomain: Add force reactivation flag to irq domains")
Signed-off-by: Thomas Gleixner <[email protected]>
Tested-by: Alexandru Chirvasitu <[email protected]>
Tested-by: Andy Shevchenko <[email protected]>
Cc: Dou Liyang <[email protected]>
Cc: Pavel Machek <[email protected]>
Cc: Maciej W. Rozycki <[email protected]>
Cc: Mikael Pettersson <[email protected]>
Cc: Josh Poulson <[email protected]>
Cc: Mihai Costache <[email protected]>
Cc: Stephen Hemminger <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: [email protected]
Cc: Haiyang Zhang <[email protected]>
Cc: Dexuan Cui <[email protected]>
Cc: Simon Xiao <[email protected]>
Cc: Saeed Mahameed <[email protected]>
Cc: Jork Loeser <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: [email protected]
Cc: KY Srinivasan <[email protected]>
Cc: Alan Cox <[email protected]>
Cc: Sakari Ailus <[email protected]>,
Cc: [email protected]

1 files changed, 27 insertions, 8 deletions

diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index edb987b2c58d..9ba954331171 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -339,6 +339,13 @@ int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
 	return ret;
 }
 
+static bool msi_check_reservation_mode(struct msi_domain_info *info)
+{
+	if (!(info->flags & MSI_FLAG_MUST_REACTIVATE))
+		return false;
+	return true;
+}
+
 /**
  * msi_domain_alloc_irqs - Allocate interrupts from a MSI interrupt domain
  * @domain:	The domain to allocate from
@@ -353,9 +360,11 @@ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
 {
 	struct msi_domain_info *info = domain->host_data;
 	struct msi_domain_ops *ops = info->ops;
-	msi_alloc_info_t arg;
+	struct irq_data *irq_data;
 	struct msi_desc *desc;
+	msi_alloc_info_t arg;
 	int i, ret, virq;
+	bool can_reserve;
 
 	ret = msi_domain_prepare_irqs(domain, dev, nvec, &arg);
 	if (ret)
@@ -385,6 +394,8 @@ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
 	if (ops->msi_finish)
 		ops->msi_finish(&arg, 0);
 
+	can_reserve = msi_check_reservation_mode(info);
+
 	for_each_msi_entry(desc, dev) {
 		virq = desc->irq;
 		if (desc->nvec_used == 1)
@@ -397,15 +408,23 @@ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
 		 * the MSI entries before the PCI layer enables MSI in the
 		 * card. Otherwise the card latches a random msi message.
 		 */
-		if (info->flags & MSI_FLAG_ACTIVATE_EARLY) {
-			struct irq_data *irq_data;
+		if (!(info->flags & MSI_FLAG_ACTIVATE_EARLY))
+			continue;
 
+		irq_data = irq_domain_get_irq_data(domain, desc->irq);
+		ret = irq_domain_activate_irq(irq_data, true);
+		if (ret)
+			goto cleanup;
+	}
+
+	/*
+	 * If these interrupts use reservation mode, clear the activated bit
+	 * so request_irq() will assign the final vector.
+	 */
+	if (can_reserve) {
+		for_each_msi_entry(desc, dev) {
 			irq_data = irq_domain_get_irq_data(domain, desc->irq);
-			ret = irq_domain_activate_irq(irq_data, true);
-			if (ret)
-				goto cleanup;
-			if (info->flags & MSI_FLAG_MUST_REACTIVATE)
-				irqd_clr_activated(irq_data);
+			irqd_clr_activated(irq_data);
 		}
 	}
 	return 0;