genirq: Teach handle_simple_irq() to resend an in-progress interrupt

It appears that the defect outlined in 9c15eeb ("genirq: Allow
fasteoi handler to resend interrupts on concurrent handling") also
affects some other less stellar MSI controllers, this time using
the handle_simple_irq() flow.

Teach this flow about irqd_needs_resend_when_in_progress(). Given
the invasive nature of this workaround, only this flow is updated.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20250708173404.1278635-2-maz@kernel.org

Author: Marc Zyngier

kernel/irq/chip.c

@@ -551,7 +551,13 @@ void handle_simple_irq(struct irq_desc *desc)
 {
 	guard(raw_spinlock)(&desc->lock);
 
-	if (!irq_can_handle(desc))
+	if (!irq_can_handle_pm(desc)) {
+		if (irqd_needs_resend_when_in_progress(&desc->irq_data))
+			desc->istate |= IRQS_PENDING;
+		return;
+	}
+
+	if (!irq_can_handle_actions(desc))
 		return;
 
 	kstat_incr_irqs_this_cpu(desc);