From: Ingo Molnar <mingo@elte.hu>
Date: Fri, 3 Jul 2009 08:29:27 -0500
Subject: x86/ioapic: Do not unmask io_apic when interrupt is in progress
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git
Git-commit: 2228245d902a479bf1ab1ebbdb6a0f50764e82d5
Patch-mainline: Queued in subsystem maintainer repository
References: SLE Realtime Extension

With threaded interrupts we might see an interrupt in progress on
migration. Do not unmask it when this is the case.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Mike Galbraith <mgalbraith@suse.de>
---
 arch/x86/kernel/apic/io_apic.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1711,7 +1711,8 @@ static bool io_apic_level_ack_pending(st
 static inline bool ioapic_irqd_mask(struct irq_data *data)
 {
 	/* If we are moving the irq we need to mask it */
-	if (unlikely(irqd_is_setaffinity_pending(data))) {
+	if (unlikely(irqd_is_setaffinity_pending(data) &&
+		     !irqd_irq_inprogress(data))) {
 		mask_ioapic_irq(data);
 		return true;
 	}