failure of acpi_register_gsi() should be handled properly

diff -puN arch/i386/kernel/acpi/boot.c~handle-error-acpi_register_gsi arch/i386/kernel/acpi/boot.c
@@ -484,7 +484,11 @@ int acpi_gsi_to_irq(u32 gsi, unsigned in
 	return 0;
 }
 
-unsigned int acpi_register_gsi(u32 gsi, int edge_level, int active_high_low)
+/*
+ * success: return IRQ number (>=0)
+ * failure: return < 0
+ */
+int acpi_register_gsi(u32 gsi, int edge_level, int active_high_low)
 {
 	unsigned int irq;
 	unsigned int plat_gsi = gsi;

diff -puN arch/ia64/kernel/acpi.c~handle-error-acpi_register_gsi arch/ia64/kernel/acpi.c
@@ -563,7 +563,11 @@ acpi_numa_arch_fixup (void)
 }
 #endif /* CONFIG_ACPI_NUMA */
 
-unsigned int
+/*
+ * success: return IRQ number (>=0)
+ * failure: return < 0
+ */
+int
 acpi_register_gsi (u32 gsi, int edge_level, int active_high_low)
 {
 	if (has_8259 && gsi < 16)

diff -puN include/linux/acpi.h~handle-error-acpi_register_gsi include/linux/acpi.h
@@ -445,7 +445,7 @@ static inline int acpi_boot_table_init(v
 
 #endif 	/*!CONFIG_ACPI_BOOT*/
 
-unsigned int acpi_register_gsi (u32 gsi, int edge_level, int active_high_low);
+int acpi_register_gsi (u32 gsi, int edge_level, int active_high_low);
 int acpi_gsi_to_irq (u32 gsi, unsigned int *irq);
 
 /*

diff -puN drivers/acpi/pci_irq.c~handle-error-acpi_register_gsi-acpi_pci_enable_irq drivers/acpi/pci_irq.c
@@ -392,6 +392,7 @@ acpi_pci_irq_enable (
 	int			edge_level = ACPI_LEVEL_SENSITIVE;
 	int			active_high_low = ACPI_ACTIVE_LOW;
 	char			*link = NULL;
+	int			rc;
 
 	ACPI_FUNCTION_TRACE("acpi_pci_irq_enable");
 

@@ -444,7 +445,13 @@ acpi_pci_irq_enable (
 		}
  	}
 
-	dev->irq = acpi_register_gsi(irq, edge_level, active_high_low);
+	rc = acpi_register_gsi(irq, edge_level, active_high_low);
+	if (rc < 0) {
+		printk(KERN_WARNING PREFIX "PCI Interrupt %s[%c]: failed "
+		       "to register GSI\n", pci_name(dev), ('A' + pin));
+		return_VALUE(rc);
+	}
+	dev->irq = rc;
 
 	printk(KERN_INFO PREFIX "PCI Interrupt %s[%c] -> ",
 		pci_name(dev), 'A' + pin);

diff -puN drivers/char/hpet.c~handle-error-acpi_register_gsi-hpet drivers/char/hpet.c
@@ -906,11 +906,15 @@ static acpi_status hpet_resources(struct
 		if (irqp->number_of_interrupts > 0) {
 			hdp->hd_nirqs = irqp->number_of_interrupts;
 
-			for (i = 0; i < hdp->hd_nirqs; i++)
-				hdp->hd_irq[i] +			for (i = 0; i < hdp->hd_nirqs; i++) {
+				int rc  				    acpi_register_gsi(irqp->interrupts[i],
 						      irqp->edge_level,
 						      irqp->active_high_low);
+				if (rc < 0)
+					return AE_ERROR;
+				hdp->hd_irq[i] = rc;
+			}
 		}
 	}
 
 

diff -puN drivers/pnp/pnpacpi/rsparser.c~handle-error-acpi_register_gsi-pnpacpi drivers/pnp/pnpacpi/rsparser.c
@@ -81,7 +81,7 @@ pnpacpi_parse_allocated_irqresource(stru
 		i++;
 	if (i < PNP_MAX_IRQ) {
 		res->irq_resource[i].flags = IORESOURCE_IRQ;  //Also clears _UNSET flag
-		if (irq = -1) {
+		if (irq < 0) {
 			res->irq_resource[i].flags |= IORESOURCE_DISABLED;
 			return;
 		}

diff -puN drivers/serial/8250_acpi.c~handle-error-acpi_register_gsi-8250_acpi drivers/serial/8250_acpi.c
@@ -47,18 +47,30 @@ static acpi_status acpi_serial_port(stru
 static acpi_status acpi_serial_ext_irq(struct uart_port *port,
 				       struct acpi_resource_ext_irq *ext_irq)
 {
-	if (ext_irq->number_of_interrupts > 0)
-		port->irq = acpi_register_gsi(ext_irq->interrupts[0],
+	int rc;
+
+	if (ext_irq->number_of_interrupts > 0) {
+		rc = acpi_register_gsi(ext_irq->interrupts[0],
 	                   ext_irq->edge_level, ext_irq->active_high_low);
+		if (rc < 0)
+			return AE_ERROR;
+		port->irq = rc;
+	}
 	return AE_OK;
 }
 
 static acpi_status acpi_serial_irq(struct uart_port *port,
 				   struct acpi_resource_irq *irq)
 {
-	if (irq->number_of_interrupts > 0)
-		port->irq = acpi_register_gsi(irq->interrupts[0],
+	int rc;
+
+	if (irq->number_of_interrupts > 0) {
+		rc = acpi_register_gsi(irq->interrupts[0],
 	                   irq->edge_level, irq->active_high_low);
+		if (rc < 0)
+			return AE_ERROR;
+		port->irq = rc;
+	}
 	return AE_OK;
 }
 

diff -puN arch/ia64/kernel/iosapic.c~handle-error-acpi_register_gsi-remove-panic-iosapic-ia64 arch/ia64/kernel/iosapic.c
@@ -561,7 +561,7 @@ static inline int vector_is_shared (int 
 	return (iosapic_intr_info[vector].count > 1);
 }
 
-static void
+static int
 register_intr (unsigned int gsi, int vector, unsigned char delivery,
 	       unsigned long polarity, unsigned long trigger)
 {

@@ -576,7 +576,7 @@ register_intr (unsigned int gsi, int vec
 	index = find_iosapic(gsi);
 	if (index < 0) {
 		printk(KERN_WARNING "%s: No IOSAPIC for GSI %u\n", __FUNCTION__, gsi);
-		return;
+		return -ENODEV;
 	}
 
 	iosapic_address = iosapic_lists[index].addr;

@@ -587,7 +587,7 @@ register_intr (unsigned int gsi, int vec
 		rte = iosapic_alloc_rte();
 		if (!rte) {
 			printk(KERN_WARNING "%s: cannot allocate memory\n", __FUNCTION__);
-			return;
+			return -ENOMEM;
 		}
 
 		rte_index = gsi - gsi_base;

@@ -603,7 +603,7 @@ register_intr (unsigned int gsi, int vec
 		struct iosapic_intr_info *info = &iosapic_intr_info[vector];
 		if (info->trigger != trigger || info->polarity != polarity) {
 			printk (KERN_WARNING "%s: cannot override the interrupt\n", __FUNCTION__);
-			return;
+			return -EINVAL;
 		}
 	}
 

@@ -623,6 +623,7 @@ register_intr (unsigned int gsi, int vec
 			       __FUNCTION__, vector, idesc->handler->typename, irq_type->typename);
 		idesc->handler = irq_type;
 	}
+	return 0;
 }
 
 static unsigned int

@@ -710,7 +711,7 @@ int
 iosapic_register_intr (unsigned int gsi,
 		       unsigned long polarity, unsigned long trigger)
 {
-	int vector, mask = 1;
+	int vector, mask = 1, err;
 	unsigned int dest;
 	unsigned long flags;
 	struct iosapic_rte_info *rte;

@@ -738,7 +739,7 @@ again:
 	if (vector < 0) {
 		vector = iosapic_find_sharable_vector(trigger, polarity);
 		if (vector < 0)
-			panic("%s: out of interrupt vectors!\n", __FUNCTION__);
+			return -ENOSPC;
 	}
 
 	spin_lock_irqsave(&irq_descp(vector)->lock, flags);

@@ -753,8 +754,13 @@ again:
 		}
 
 		dest = get_target_cpu(gsi, vector);
-		register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY,
+		err = register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY,
 			      polarity, trigger);
+		if (err < 0) {
+			spin_unlock(&iosapic_lock);
+			spin_unlock_irqrestore(&irq_descp(vector)->lock, flags);
+			return err;
+		}
 
 		/*
 		 * If the vector is shared and already unmasked for