From c1797b11a09c8323c92b074fd48b89a936c991d0 Mon Sep 17 00:00:00 2001 From: Yang Yingliang Date: Fri, 22 Jun 2018 10:52:51 +0100 Subject: [PATCH] irqchip/gic-v3-its: Don't bind LPI to unavailable NUMA node On a NUMA system, if an ITS is local to an offline node, the ITS driver may pick an offline CPU to bind the LPI. In this case, pick an online CPU (and the first one will do). But on some systems, binding an LPI to non-local node CPU may cause deadlock (see Cavium erratum 23144). In this case, just fail the activate and return an error code. Signed-off-by: Yang Yingliang Signed-off-by: Marc Zyngier Signed-off-by: Thomas Gleixner Cc: Jason Cooper Cc: Alexandre Belloni Cc: Sumit Garg Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180622095254.5906-5-marc.zyngier@arm.com --- drivers/irqchip/irq-gic-v3-its.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 5377d7e2afba..cae53937feeb 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -2310,7 +2310,14 @@ static int its_irq_domain_activate(struct irq_domain *domain, cpu_mask = cpumask_of_node(its_dev->its->numa_node); /* Bind the LPI to the first possible CPU */ - cpu = cpumask_first(cpu_mask); + cpu = cpumask_first_and(cpu_mask, cpu_online_mask); + if (cpu >= nr_cpu_ids) { + if (its_dev->its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_23144) + return -EINVAL; + + cpu = cpumask_first(cpu_online_mask); + } + its_dev->event_map.col_map[event] = cpu; irq_data_update_effective_affinity(d, cpumask_of(cpu)); -- 2.30.2