[PATCH] x86/ioapic: add IO-APIC irq_chip retrigger hook

From: Ruslan Ruslichenko
Date: Tue Jan 17 2017 - 09:22:58 EST


After commit d32932d02e18 ("x86/irq: Convert IOAPIC to use hierarchical
irqdomain interfaces") IO-APIC is switched to hierarchical irqdomain
implementation. Also this patch removed irq_retrigger hook for IO-APIC
chip which seem to be wrong. Without this hook some edge-triggered irq's
might be lost, since kernel uses it to retrigger edge irq's triggered
while they are being handled or disabled by driver
(see "Delayed_interrupt_disable" section at "Generic-IRQ-Guide"
of kernel docbook).

Thus adding this hook same way as it was done for MSI domain.

Signed-off-by: Ruslan Ruslichenko <rruslich@xxxxxxxxx>
---
arch/x86/kernel/apic/io_apic.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 945e512..1e35dd0 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1875,6 +1875,7 @@ static int ioapic_set_affinity(struct irq_data *irq_data,
.irq_ack = irq_chip_ack_parent,
.irq_eoi = ioapic_ack_level,
.irq_set_affinity = ioapic_set_affinity,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
.flags = IRQCHIP_SKIP_SET_WAKE,
};

@@ -1886,6 +1887,7 @@ static int ioapic_set_affinity(struct irq_data *irq_data,
.irq_ack = irq_chip_ack_parent,
.irq_eoi = ioapic_ir_ack_level,
.irq_set_affinity = ioapic_set_affinity,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
.flags = IRQCHIP_SKIP_SET_WAKE,
};

--
1.9.1