[PATCH AUTOSEL for 4.9 206/293] irqchip/gic-v3: Honor forced affinity setting

From: Sasha Levin
Date: Sun Apr 08 2018 - 22:00:23 EST


From: Suzuki K Poulose <suzuki.poulose@xxxxxxx>

[ Upstream commit 65a30f8b300107266f316d550f060ccc186201a3 ]

Honor the 'force' flag for set_affinity, by selecting a CPU
from the given mask (which may not be reported "online" by
the cpu_online_mask). Some drivers, like ARM PMU, rely on it.

Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
Reported-by: Mark Rutland <mark.rutland@xxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/irqchip/irq-gic-v3.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 8c7f02318a6b..0ef240c64c65 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -641,11 +641,16 @@ static void gic_smp_init(void)
static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
bool force)
{
- unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
+ unsigned int cpu;
void __iomem *reg;
int enabled;
u64 val;

+ if (force)
+ cpu = cpumask_first(mask_val);
+ else
+ cpu = cpumask_any_and(mask_val, cpu_online_mask);
+
if (cpu >= nr_cpu_ids)
return -EINVAL;

--
2.15.1