[PATCH AUTOSEL 4.20 20/77] genirq: Make sure the initial affinity is not empty

Sasha Levin
2019-02-15T02:41:45Z

From: Srinivas Ramana <sramana@codeaurora.org>

[ Upstream commit bddda606ec76550dd63592e32a6e87e7d32583f7 ]

If all CPUs in the irq_default_affinity mask are offline when an interrupt
is initialized then irq_setup_affinity() can set an empty affinity mask for
a newly allocated interrupt.

Fix this by falling back to cpu_online_mask in case the resulting affinity
mask is zero.

Signed-off-by: Srinivas Ramana <sramana@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-msm@vger.kernel.org
Link: https://lkml.kernel.org/r/1545312957-8504-1-git-send-email-sramana@codeaurora.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
kernel/irq/manage.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 9dbdccab3b6a..5c0ba5ca5930 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -393,6 +393,9 @@ int irq_setup_affinity(struct irq_desc *desc)
}

cpumask_and(&mask, cpu_online_mask, set);
+ if (cpumask_empty(&mask))
+ cpumask_copy(&mask, cpu_online_mask);
+
if (node != NUMA_NO_NODE) {
const struct cpumask *nodemask = cpumask_of_node(node);

--
2.19.1