x86, io-apic: Don't mark pin_programmed early

Peter bisected that:

| commit b9c61b70075c87a8612624736faf4a2de5b1ed30
| Date:   Wed May 6 10:10:06 2009 -0700
|
|     x86/pci: update pirq_enable_irq() to setup io apic routing
|
|     So we can set io apic routing only when enabling the device irq.

wrecked his opteron box, ata1 interrupts fail to get through.

ata1 is using irq 11:

[    1.451839] sata_svw 0000:01:0e.0: version 2.3
[    1.456333] sata_svw 0000:01:0e.0: PCI INT A -> GSI 11 (level, low) -> IRQ 11
[    1.463639] scsi0 : sata_svw
[    1.466949] scsi1 : sata_svw
[    1.470022] scsi2 : sata_svw
[    1.473090] scsi3 : sata_svw
[    1.476112] ata1: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe000 irq 11
[    1.483490] ata2: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe100 irq 11
[    1.490870] ata3: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe200 irq 11
[    1.498247] ata4: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe300 irq 11

that pin is overlapped with pin with legacy ones.

We should not set bits in pin_programmed here, so that those bit could
be set later via io_apic_set_pci_routing().

[ Impact: fix boot hang on certain systems ]

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org>
Tested-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jack Steiner <steiner@sgi.com>
LKML-Reference: <4A119990.9020606@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/apic/io_apic.c

@@ -1537,7 +1537,10 @@ static void __init setup_IO_APIC_irqs(void)
 		}
 		cfg = desc->chip_data;
 		add_pin_to_irq_node(cfg, node, apic_id, pin);
-		set_bit(pin, mp_ioapic_routing[apic_id].pin_programmed);
+		/*
+		 * don't mark it in pin_programmed, so later acpi could
+		 * set it correctly when irq < 16
+		 */
 		setup_IO_APIC_irq(apic_id, pin, irq, desc,
 				irq_trigger(idx), irq_polarity(idx));
 	}