[patch 1/5] ia64: Validate online cpus in irq_set_affinity() callbacks

[Thomas Gleixner <tglx@linutronix.de>]

The [user space] interface does not filter out offline cpus. It merily
guarantees that the mask contains at least one online cpu.

So the selector in the irq chip implementation needs to make sure to
pick only an online cpu because otherwise:

     Offline Core 1
     Set affinity to 0xe (is valid due to online mask 0xd)
     cpumask_first will pick core 1, which is offline

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: ia64 <linux-ia64@vger.kernel.org>
---
 arch/ia64/kernel/msi_ia64.c  |    5 +----
 arch/ia64/sn/kernel/irq.c    |    4 ++--
 arch/ia64/sn/kernel/msi_sn.c |    2 +-
 3 files changed, 4 insertions(+), 7 deletions(-)

Index: tip/arch/ia64/kernel/msi_ia64.c
=================================--- tip.orig/arch/ia64/kernel/msi_ia64.c
+++ tip/arch/ia64/kernel/msi_ia64.c
@@ -17,12 +17,9 @@ static int ia64_set_msi_irq_affinity(str
 {
 	struct msi_msg msg;
 	u32 addr, data;
-	int cpu = first_cpu(*cpu_mask);
+	int cpu = cpumask_first_and(cpu_mask, cpu_online_mask);
 	unsigned int irq = idata->irq;
 
-	if (!cpu_online(cpu))
-		return -1;
-
 	if (irq_prepare_move(irq, cpu))
 		return -1;
 
Index: tip/arch/ia64/sn/kernel/irq.c
=================================--- tip.orig/arch/ia64/sn/kernel/irq.c
+++ tip/arch/ia64/sn/kernel/irq.c
@@ -209,8 +209,8 @@ static int sn_set_affinity_irq(struct ir
 	nasid_t nasid;
 	int slice;
 
-	nasid = cpuid_to_nasid(cpumask_first(mask));
-	slice = cpuid_to_slice(cpumask_first(mask));
+	nasid = cpuid_to_nasid(cpumask_first_and(mask, cpu_online_mask));
+	slice = cpuid_to_slice(cpumask_first_and(mask, cpu_online_mask));
 
 	list_for_each_entry_safe(sn_irq_info, sn_irq_info_safe,
 				 sn_irq_lh[irq], list)
Index: tip/arch/ia64/sn/kernel/msi_sn.c
=================================--- tip.orig/arch/ia64/sn/kernel/msi_sn.c
+++ tip/arch/ia64/sn/kernel/msi_sn.c
@@ -166,7 +166,7 @@ static int sn_set_msi_irq_affinity(struc
 	struct sn_pcibus_provider *provider;
 	unsigned int cpu, irq = data->irq;
 
-	cpu = cpumask_first(cpu_mask);
+	cpu = cpumask_first_and(cpu_mask, cpu_online_mask);
 	sn_irq_info = sn_msi_info[irq].sn_irq_info;
 	if (sn_irq_info = NULL || sn_irq_info->irq_int_bit >= 0)
 		return -1;