[PATCH AUTOSEL 4.20 30/81] irqchip/gic-v3-its: Gracefully fail on LPI exhaustion

Sasha Levin
2019-02-28T15:32:22Z

From: Marc Zyngier <marc.zyngier@arm.com>

[ Upstream commit 45725e0fc3e7fe52fedb94f59806ec50e9618682 ]

In the unlikely event that we cannot find any available LPI in the
system, we should gracefully return an error instead of carrying
on with no LPI allocated at all.

Fixes: 38dd7c494cf6 ("irqchip/gic-v3-its: Drop chunk allocation compatibility")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/irqchip/irq-gic-v3-its.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index f25ec92f23ee2..c3aba3fc818d3 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1586,6 +1586,9 @@ static unsigned long *its_lpi_alloc(int nr_irqs, u32 *base, int *nr_ids)
nr_irqs /= 2;
} while (nr_irqs > 0);

+ if (!nr_irqs)
+ err = -ENOSPC;
+
if (err)
goto out;

--
2.19.1