---

yaml
---
r: 3901
b: refs/heads/master
c: 200803d
h: refs/heads/master
i:
  3899: 05a412d
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 21fe3471c3aaa5c489c5d3a4d705291eb7511248
+refs/heads/master: 200803dfe4ff772740d63db725ab2f1b185ccf92

trunk/Documentation/kernel-parameters.txt

@@ -437,6 +437,10 @@ running once the system is up.
 			Format: {"of[f]" | "sk[ipmbr]"}
 			See comment in arch/i386/boot/edd.S
 
+	edd		[EDD]
+			Format: {"of[f]" | "sk[ipmbr]"}
+			See comment in arch/i386/boot/edd.S
+
 	eicon=		[HW,ISDN] 
 			Format: <id>,<membase>,<irq>
 
@@ -622,6 +626,17 @@ running once the system is up.
 	ips=		[HW,SCSI] Adaptec / IBM ServeRAID controller
 			See header of drivers/scsi/ips.c.
 
+	irqfixup	[HW]
+			When an interrupt is not handled search all handlers
+			for it. Intended to get systems with badly broken
+			firmware running.
+
+	irqpoll		[HW]
+			When an interrupt is not handled search all handlers
+			for it. Also check all handlers each timer
+			interrupt. Intended to get systems with badly broken
+			firmware running.
+
 	isapnp=		[ISAPNP]
 			Format: <RDP>, <reset>, <pci_scan>, <verbosity>
 

trunk/arch/ppc64/kernel/irq.c

@@ -245,7 +245,7 @@ void ppc_irq_dispatch_handler(struct pt_regs *regs, int irq)
 
 		spin_lock(&desc->lock);
 		if (!noirqdebug)
-			note_interrupt(irq, desc, action_ret);
+			note_interrupt(irq, desc, action_ret, regs);
 		if (likely(!(desc->status & IRQ_PENDING)))
 			break;
 		desc->status &= ~IRQ_PENDING;

trunk/include/linux/irq.h

@@ -85,9 +85,10 @@ extern int no_irq_affinity;
 extern int noirqdebug_setup(char *str);
 
 extern fastcall int handle_IRQ_event(unsigned int irq, struct pt_regs *regs,
-				       struct irqaction *action);
+					struct irqaction *action);
 extern fastcall unsigned int __do_IRQ(unsigned int irq, struct pt_regs *regs);
-extern void note_interrupt(unsigned int irq, irq_desc_t *desc, int action_ret);
+extern void note_interrupt(unsigned int irq, irq_desc_t *desc,
+					int action_ret, struct pt_regs *regs);
 extern int can_request_irq(unsigned int irq, unsigned long irqflags);
 
 extern void init_irq_proc(void);

trunk/kernel/irq/handle.c

@@ -172,7 +172,7 @@ fastcall unsigned int __do_IRQ(unsigned int irq, struct pt_regs *regs)
 
 		spin_lock(&desc->lock);
 		if (!noirqdebug)
-			note_interrupt(irq, desc, action_ret);
+			note_interrupt(irq, desc, action_ret, regs);
 		if (likely(!(desc->status & IRQ_PENDING)))
 			break;
 		desc->status &= ~IRQ_PENDING;

trunk/kernel/irq/spurious.c

@@ -11,6 +11,83 @@
 #include <linux/kallsyms.h>
 #include <linux/interrupt.h>
 
+static int irqfixup;
+
+/*
+ * Recovery handler for misrouted interrupts.
+ */
+
+static int misrouted_irq(int irq, struct pt_regs *regs)
+{
+	int i;
+	irq_desc_t *desc;
+	int ok = 0;
+	int work = 0;	/* Did we do work for a real IRQ */
+
+	for(i = 1; i < NR_IRQS; i++) {
+		struct irqaction *action;
+
+		if (i == irq)	/* Already tried */
+			continue;
+		desc = &irq_desc[i];
+		spin_lock(&desc->lock);
+		action = desc->action;
+		/* Already running on another processor */
+		if (desc->status & IRQ_INPROGRESS) {
+			/*
+			 * Already running: If it is shared get the other
+			 * CPU to go looking for our mystery interrupt too
+			 */
+			if (desc->action && (desc->action->flags & SA_SHIRQ))
+				desc->status |= IRQ_PENDING;
+			spin_unlock(&desc->lock);
+			continue;
+		}
+		/* Honour the normal IRQ locking */
+		desc->status |= IRQ_INPROGRESS;
+		spin_unlock(&desc->lock);
+		while (action) {
+			/* Only shared IRQ handlers are safe to call */
+			if (action->flags & SA_SHIRQ) {
+				if (action->handler(i, action->dev_id, regs) ==
+						IRQ_HANDLED)
+					ok = 1;
+			}
+			action = action->next;
+		}
+		local_irq_disable();
+		/* Now clean up the flags */
+		spin_lock(&desc->lock);
+		action = desc->action;
+
+		/*
+		 * While we were looking for a fixup someone queued a real
+		 * IRQ clashing with our walk
+		 */
+
+		while ((desc->status & IRQ_PENDING) && action) {
+			/*
+			 * Perform real IRQ processing for the IRQ we deferred
+			 */
+			work = 1;
+			spin_unlock(&desc->lock);
+			handle_IRQ_event(i, regs, action);
+			spin_lock(&desc->lock);
+			desc->status &= ~IRQ_PENDING;
+		}
+		desc->status &= ~IRQ_INPROGRESS;
+		/*
+		 * If we did actual work for the real IRQ line we must let the
+		 * IRQ controller clean up too
+		 */
+		if(work)
+			desc->handler->end(i);
+		spin_unlock(&desc->lock);
+	}
+	/* So the caller can adjust the irq error counts */
+	return ok;
+}
+
 /*
  * 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
@@ -31,7 +108,8 @@ __report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret)
 		printk(KERN_ERR "irq event %d: bogus return value %x\n",
 				irq, action_ret);
 	} else {
-		printk(KERN_ERR "irq %d: nobody cared!\n", irq);
+		printk(KERN_ERR "irq %d: nobody cared (try booting with "
+				"the \"irqpoll\" option)\n", irq);
 	}
 	dump_stack();
 	printk(KERN_ERR "handlers:\n");
@@ -55,14 +133,24 @@ static void report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t actio
 	}
 }
 
-void note_interrupt(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret)
+void note_interrupt(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret,
+			struct pt_regs *regs)
 {
 	if (action_ret != IRQ_HANDLED) {
 		desc->irqs_unhandled++;
 		if (action_ret != IRQ_NONE)
 			report_bad_irq(irq, desc, action_ret);
 	}
 
+	if (unlikely(irqfixup)) {
+		/* Don't punish working computers */
+		if ((irqfixup == 2 && irq == 0) || action_ret == IRQ_NONE) {
+			int ok = misrouted_irq(irq, regs);
+			if (action_ret == IRQ_NONE)
+				desc->irqs_unhandled -= ok;
+		}
+	}
+
 	desc->irq_count++;
 	if (desc->irq_count < 100000)
 		return;
@@ -94,3 +182,24 @@ int __init noirqdebug_setup(char *str)
 
 __setup("noirqdebug", noirqdebug_setup);
 
+static int __init irqfixup_setup(char *str)
+{
+	irqfixup = 1;
+	printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n");
+	printk(KERN_WARNING "This may impact system performance.\n");
+	return 1;
+}
+
+__setup("irqfixup", irqfixup_setup);
+
+static int __init irqpoll_setup(char *str)
+{
+	irqfixup = 2;
+	printk(KERN_WARNING "Misrouted IRQ fixup and polling support "
+				"enabled\n");
+	printk(KERN_WARNING "This may significantly impact system "
+				"performance\n");
+	return 1;
+}
+
+__setup("irqpoll", irqpoll_setup);