NUMA-Q breakage 3/7 irqbalance stuffs unreachable cpu's in IO-APICS

[William Lee Irwin III]

irqbalance stuffs unreachable cpus' APIC ID's into the IO-APICs.
This cannot be done generically, as the cpu's that can be reached
from a given IO-APIC depend on the subarch. The net effect of the bug
is deadlocking while waiting for interrupts to come back from devices,
i.e. booting is impossible.

Fix (due to Matt Dobson) below.

Cheers,
Bill

diff -Nur linux-2.5.23-vanilla/arch/i386/kernel/io_apic.c linux-2.5.23-patched/arch/i386/kernel/io_apic.c
--- linux-2.5.23-vanilla/arch/i386/kernel/io_apic.c	Tue Jun 18 19:11:52 2002
+++ linux-2.5.23-patched/arch/i386/kernel/io_apic.c	Thu Jun 27 14:28:51 2002
@@ -247,7 +247,7 @@
 
 static inline void balance_irq(int irq)
 {
-#if CONFIG_SMP
+#if (CONFIG_SMP && !CONFIG_MULTIQUAD)
 	irq_balance_t *entry = irq_balance + irq;
 	unsigned long now = jiffies;