[patch 2/7] x86/lguest: Do not setup unused irq vectors

[Thomas Gleixner <tglx@linutronix.de>]

[-- Attachment #1: x86-lguest--Do-not-setup-unused-irq-vectors --]
[-- Type: text/plain, Size: 1752 bytes --]

No point in assigning the interrupt vectors if there is no interrupt
chip installed. Move it to lguest_setup_irq().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
---
 arch/x86/lguest/boot.c |   13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

Index: tip/arch/x86/lguest/boot.c
===================================================================
--- tip.orig/arch/x86/lguest/boot.c
+++ tip/arch/x86/lguest/boot.c
@@ -855,17 +855,13 @@ static void lguest_disable_irq(struct pc
 
 /*
  * This sets up the Interrupt Descriptor Table (IDT) entry for each hardware
- * interrupt (except 128, which is used for system calls), and then tells the
- * Linux infrastructure that each interrupt is controlled by our level-based
- * lguest interrupt controller.
+ * interrupt (except 128, which is used for system calls).
  */
 static void __init lguest_init_IRQ(void)
 {
 	unsigned int i;
 
 	for (i = FIRST_EXTERNAL_VECTOR; i < FIRST_SYSTEM_VECTOR; i++) {
-		/* Some systems map "vectors" to interrupts weirdly.  Not us! */
-		__this_cpu_write(vector_irq[i], i - FIRST_EXTERNAL_VECTOR);
 		if (i != IA32_SYSCALL_VECTOR)
 			set_intr_gate(i, irq_entries_start +
 					8 * (i - FIRST_EXTERNAL_VECTOR));
@@ -893,8 +889,15 @@ int lguest_setup_irq(unsigned int irq)
 	if (err < 0 && err != -EEXIST)
 		return err;
 
+	/*
+	 * Tell the Linux infrastructure that the interrupt is
+	 * controlled by our level-based lguest interrupt controller.
+	 */
 	irq_set_chip_and_handler_name(irq, &lguest_irq_controller,
 				      handle_level_irq, "level");
+
+	/* Some systems map "vectors" to interrupts weirdly.  Not us! */
+	__this_cpu_write(vector_irq[FIRST_EXTERNAL_VECTOR + irq, irq);
 	return 0;
 }