[patch 2/2] genirq: Add reentrancy warning messages

[Thomas Gleixner <tglx@linutronix.de>]

[-- Attachment #1: genirq-add-reentrancy-messages.patch --]
[-- Type: text/plain, Size: 1554 bytes --]


The simple and level irq handlers prevent reentrancy. For those irq types
reentrancy should not happen. Instead of silently going back omit a warning
message. Also do not reenable the interrupt in that case.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

 kernel/irq/chip.c |   12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

Index: linux-2.6.17-rc6-mm/kernel/irq/chip.c
===================================================================
--- linux-2.6.17-rc6-mm.orig/kernel/irq/chip.c	2006-06-10 10:32:49.000000000 +0200
+++ linux-2.6.17-rc6-mm/kernel/irq/chip.c	2006-06-10 10:42:40.000000000 +0200
@@ -208,8 +208,11 @@
 
 	spin_lock(&desc->lock);
 
-	if (unlikely(desc->status & IRQ_INPROGRESS))
+	if (unlikely(desc->status & IRQ_INPROGRESS)) {
+		printk(KERN_ERR "handle_simple_irq reentered while "
+		       "processing irq %d\n", irq);
 		goto out_unlock;
+	}
 	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
 	kstat_cpu(cpu).irqs[irq]++;
 
@@ -251,8 +254,11 @@
 	spin_lock(&desc->lock);
 	mask_ack_irq(desc, irq);
 
-	if (unlikely(desc->status & IRQ_INPROGRESS))
+	if (unlikely(desc->status & IRQ_INPROGRESS)) {
+		printk(KERN_ERR "handle_level_irq reentered while "
+		       "processing irq %d\n", irq);
 		goto out;
+	}
 	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
 	kstat_cpu(cpu).irqs[irq]++;
 
@@ -273,9 +279,9 @@
 
 	spin_lock(&desc->lock);
 	desc->status &= ~IRQ_INPROGRESS;
-out:
 	if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
 		desc->chip->unmask(irq);
+out:
 	spin_unlock(&desc->lock);
 }
 

--