genirq: Make sure the initial affinity is not empty

[ 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 <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Sasha Levin <[email protected]>
akeromi · Mar 5, 2019 · 17fab89 · 17fab89
1 parent 7746dd6
commit 17fab89
Showing 1 changed file with 3 additions and 0 deletions.
diff --git 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);