1 files changed, 96 insertions, 0 deletions

diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
new file mode 100644
index 000000000000..f6297c306905
--- /dev/null
+++ b/kernel/irq/spurious.c
@@ -0,0 +1,96 @@
+/*
+ * linux/kernel/irq/spurious.c
+ *
+ * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
+ *
+ * This file contains spurious interrupt handling.
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/interrupt.h>
+
+/*
+ * If 99,900 of the previous 100,000 interrupts have not been handled
+ * then assume that the IRQ is stuck in some manner. Drop a diagnostic
+ * and try to turn the IRQ off.
+ *
+ * (The other 100-of-100,000 interrupts may have been a correctly
+ *  functioning device sharing an IRQ with the failing one)
+ *
+ * Called under desc->lock
+ */
+
+static void
+__report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret)
+{
+        struct irqaction *action;
+
+        if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) {
+                printk(KERN_ERR "irq event %d: bogus return value %x\n",
+                                irq, action_ret);
+        } else {
+                printk(KERN_ERR "irq %d: nobody cared!\n", irq);
+        }
+        dump_stack();
+        printk(KERN_ERR "handlers:\n");
+        action = desc->action;
+        while (action) {
+                printk(KERN_ERR "[<%p>]", action->handler);
+                print_symbol(" (%s)",
+                        (unsigned long)action->handler);
+                printk("\n");
+                action = action->next;
+        }
+}
+
+void report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret)
+{
+        static int count = 100;
+
+        if (count > 0) {
+                count--;
+                __report_bad_irq(irq, desc, action_ret);
+        }
+}
+
+void note_interrupt(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret)
+{
+        if (action_ret != IRQ_HANDLED) {
+                desc->irqs_unhandled++;
+                if (action_ret != IRQ_NONE)
+                        report_bad_irq(irq, desc, action_ret);
+        }
+
+        desc->irq_count++;
+        if (desc->irq_count < 100000)
+                return;
+
+        desc->irq_count = 0;
+        if (desc->irqs_unhandled > 99900) {
+                /*
+                 * The interrupt is stuck
+                 */
+                __report_bad_irq(irq, desc, action_ret);
+                /*
+                 * Now kill the IRQ
+                 */
+                printk(KERN_EMERG "Disabling IRQ #%d\n", irq);
+                desc->status |= IRQ_DISABLED;
+                desc->handler->disable(irq);
+        }
+        desc->irqs_unhandled = 0;
+}
+
+int noirqdebug;
+
+int __init noirqdebug_setup(char *str)
+{
+        noirqdebug = 1;
+        printk(KERN_INFO "IRQ lockup detection disabled\n");
+        return 1;
+}
+
+__setup("noirqdebug", noirqdebug_setup);
+