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: David Stevens <stevensd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240424090341.72236-1-stevensd@chromium.org

diff --git a/kernel/irq/cpuhotplug.c b/kernel/irq/cpuhotplug.c
index 1ed2b1739363b855bee1404e35f5c036056bdd1f..43340e0b6df058c15f95591ed70612139807214d 100644 (file)
--- a/kernel/irq/cpuhotplug.c
+++ b/kernel/irq/cpuhotplug.c
@@ -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

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index ad3eaf2ab959616104fb7192c3cb64e935ca43f3..29c378d096aa4dc9e62691488b7bf7184abbeae3 100644 (file)
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -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;