[PATCH 5.8 006/232] genirq/PM: Always unlock IRQ descriptor in rearm_wake_irq()

[Greg Kroah-Hartman]

From: Guenter Roeck <linux@xxxxxxxxxxxx>

commit e27b1636e9337d1a1d174b191e53d0f86421a822 upstream.

rearm_wake_irq() does not unlock the irq descriptor if the interrupt
is not suspended or if wakeup is not enabled on it.

Restucture the exit conditions so the unlock is always ensured.

Fixes: 3a79bc63d9075 ("PCI: irq: Introduce rearm_wake_irq()")
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20200811180001.80203-1-linux@xxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 kernel/irq/pm.c |    8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

--- a/kernel/irq/pm.c
+++ b/kernel/irq/pm.c
@@ -185,14 +185,18 @@ void rearm_wake_irq(unsigned int irq)
 	unsigned long flags;
 	struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
 
-	if (!desc || !(desc->istate & IRQS_SUSPENDED) ||
-	    !irqd_is_wakeup_set(&desc->irq_data))
+	if (!desc)
 		return;
 
+	if (!(desc->istate & IRQS_SUSPENDED) ||
+	    !irqd_is_wakeup_set(&desc->irq_data))
+		goto unlock;
+
 	desc->istate &= ~IRQS_SUSPENDED;
 	irqd_set(&desc->irq_data, IRQD_WAKEUP_ARMED);
 	__enable_irq(desc);
 
+unlock:
 	irq_put_desc_busunlock(desc, flags);
 }