x86/irq: Make irq activate operations symmetric

The recent commit which prevents double activation of interrupts unearthed
interesting code in x86. The code (ab)uses irq_domain_activate_irq() to
reconfigure an already activated interrupt. That trips over the prevention
code now.

Fix it by deactivating the interrupt before activating the new configuration.

Fixes: 08d85f3ea99f1 "irqdomain: Avoid activating interrupts more than once"
Reported-and-tested-by: Mike Galbraith <[email protected]>
Reported-and-tested-by: Borislav Petkov <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Andrey Ryabinin <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701311901580.3457@nanos

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 1e35dd06b090ee91189cb5a52fdf026f2ca5e74b..52f352b063fdf372bddd62d5887296fa43661931 100644 (file)
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2117,6 +2117,7 @@ static inline void __init check_timer(void)
                        if (idx != -1 && irq_trigger(idx))
                                unmask_ioapic_irq(irq_get_chip_data(0));
                }
+               irq_domain_deactivate_irq(irq_data);
                irq_domain_activate_irq(irq_data);
                if (timer_irq_works()) {
                        if (disable_timer_pin_1 > 0)
@@ -2138,6 +2139,7 @@ static inline void __init check_timer(void)
                 * legacy devices should be connected to IO APIC #0
                 */
                replace_pin_at_irq_node(data, node, apic1, pin1, apic2, pin2);
+               irq_domain_deactivate_irq(irq_data);
                irq_domain_activate_irq(irq_data);
                legacy_pic->unmask(0);
                if (timer_irq_works()) {

diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index 85e87b46c318026ed28d87056c516aec3e5fb9ed..dc6ba5bda9fc83630c773a80c4adea6871db0a59 100644 (file)
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -352,6 +352,7 @@ static int hpet_resume(struct clock_event_device *evt, int timer)
        } else {
                struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt);
 
+               irq_domain_deactivate_irq(irq_get_irq_data(hdev->irq));
                irq_domain_activate_irq(irq_get_irq_data(hdev->irq));
                disable_irq(hdev->irq);
                irq_set_affinity(hdev->irq, cpumask_of(hdev->cpu));