genirq: Take the proposed affinity at face value if force==true
Although setting the affinity of an interrupt to a set of CPUs
that doesn't have any online CPU is generally frowned apon,
there are a few limited cases where such affinity is set from
a CPUHP notifier, setting the affinity to a CPU that isn't online
yet.
The saving grace is that this is always done using the 'force'
attribute, which gives us a hint that we really shouldn't worry
too much about the affinity at this stage, and that the caller
knows best. Or so we hope.
This restores the expected behaviour on Marek's system.
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link:: https://lore.kernel.org/r/4b7fc13c-887b-a664-26e8-45aed13f048a@samsung.com
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index f71ecc1..f1d5a94 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -266,10 +266,16 @@
prog_mask = mask;
}
- /* Make sure we only provide online CPUs to the irqchip */
+ /*
+ * Make sure we only provide online CPUs to the irqchip,
+ * unless we are being asked to force the affinity (in which
+ * case we do as we are told).
+ */
cpumask_and(&tmp_mask, prog_mask, cpu_online_mask);
- if (!cpumask_empty(&tmp_mask))
+ if (!force && !cpumask_empty(&tmp_mask))
ret = chip->irq_set_affinity(data, &tmp_mask, force);
+ else if (force)
+ ret = chip->irq_set_affinity(data, mask, force);
else
ret = -EINVAL;
