[PATCH] ppc64: update irq affinity mask when migrating irqs

This patch is from Nathan Lynch <ntl@pobox.com>.

When offlining a cpu, any device interrupts which are bound to the cpu
have their affinity forcibly reset to all cpus (the default).
However, the value in /proc/irq/XXX/smp_affinity remains unchanged.
Since we're doing this while all the other cpus are stopped, it should
be safe to just call desc->handler->set_affinity and manually update
the irq_affinity array.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/ppc64/kernel/xics.c

@@ -704,15 +704,8 @@ void xics_migrate_irqs_away(void)
 		       virq, cpu);
 
 		/* Reset affinity to all cpus */
-		xics_status[0] = default_distrib_server;
-
-		status = rtas_call(ibm_set_xive, 3, 1, NULL, irq,
-				xics_status[0], xics_status[1]);
-		if (status)
-			printk(KERN_ERR "migrate_irqs_away: irq=%d "
-					"ibm,set-xive returns %d\n",
-					virq, status);
-
+		desc->handler->set_affinity(virq, CPU_MASK_ALL);
+		irq_affinity[virq] = CPU_MASK_ALL;
 unlock:
 		spin_unlock_irqrestore(&desc->lock, flags);
 	}