Commit a60dd06a authored by David Stevens's avatar David Stevens Committed by Thomas Gleixner
Browse files

genirq/cpuhotplug: Skip suspended interrupts when restoring affinity 



irq_restore_affinity_of_irq() restarts managed interrupts unconditionally
when the first CPU in the affinity mask comes online. That's correct during
normal hotplug operations, but not when resuming from S3 because the
drivers are not resumed yet and interrupt delivery is not expected by them.

Skip the startup of suspended interrupts and let resume_device_irqs() deal
with restoring them. This ensures that irqs are not delivered to drivers
during the noirq phase of resuming from S3, after non-boot CPUs are brought
back online.

Signed-off-by: default avatarDavid Stevens <stevensd@chromium.org>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240424090341.72236-1-stevensd@chromium.org
parent 7da4ba31

kernel/irq/cpuhotplug.c

+8 −3
Original line number Diff line number Diff line
@@ -195,10 +195,15 @@ static void irq_restore_affinity_of_irq(struct irq_desc *desc, unsigned int cpu) 
	    !irq_data_get_irq_chip(data) || !cpumask_test_cpu(cpu, affinity))

		return;



	if (irqd_is_managed_and_shutdown(data)) {

		irq_startup(desc, IRQ_RESEND, IRQ_START_COND);

	/*

	 * Don't restore suspended interrupts here when a system comes back

	 * from S3. They are reenabled via resume_device_irqs().

	 */

	if (desc->istate & IRQS_SUSPENDED)

		return;

	}



	if (irqd_is_managed_and_shutdown(data))

		irq_startup(desc, IRQ_RESEND, IRQ_START_COND);



	/*

	 * If the interrupt can only be directed to a single target

kernel/irq/manage.c

+8 −4
Original line number Diff line number Diff line
@@ -800,10 +800,14 @@ void __enable_irq(struct irq_desc *desc) 
		irq_settings_set_noprobe(desc);

		/*

		 * Call irq_startup() not irq_enable() here because the

		 * interrupt might be marked NOAUTOEN. So irq_startup()

		 * needs to be invoked when it gets enabled the first

		 * time. If it was already started up, then irq_startup()

		 * will invoke irq_enable() under the hood.

		 * interrupt might be marked NOAUTOEN so irq_startup()

		 * needs to be invoked when it gets enabled the first time.

		 * This is also required when __enable_irq() is invoked for

		 * a managed and shutdown interrupt from the S3 resume

		 * path.

		 *

		 * If it was already started up, then irq_startup() will

		 * invoke irq_enable() under the hood.

		 */

		irq_startup(desc, IRQ_RESEND, IRQ_START_FORCE);

		break;