From 544808f7e21cb9ccdb8f3aa7de594c05b1419061 Mon Sep 17 00:00:00 2001
From: Andre Przywara <andre.przywara@arm.com>
Date: Mon, 4 Apr 2022 12:08:42 +0100
Subject: [PATCH] irqchip/gic, gic-v3: Prevent GSI to SGI translations
Git-commit: 544808f7e21cb9ccdb8f3aa7de594c05b1419061
Patch-mainline: v5.18-rc2
References: git-fixes
At the moment the GIC IRQ domain translation routine happily converts
ACPI table GSI numbers below 16 to GIC SGIs (Software Generated
Interrupts aka IPIs). On the Devicetree side we explicitly forbid this
translation, actually the function will never return HWIRQs below 16 when
using a DT based domain translation.
We expect SGIs to be handled in the first part of the function, and any
further occurrence should be treated as a firmware bug, so add a check
and print to report this explicitly and avoid lengthy debug sessions.
Fixes: 64b499d8df40 ("irqchip/gic-v3: Configure SGIs as standard interrupts")
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220404110842.2882446-1-andre.przywara@arm.com
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/irqchip/irq-gic-v3.c | 6 ++++++
drivers/irqchip/irq-gic.c | 6 ++++++
2 files changed, 12 insertions(+)
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 9b6316582515..b252d5534547 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -1466,6 +1466,12 @@ static int gic_irq_domain_translate(struct irq_domain *d,
if(fwspec->param_count != 2)
return -EINVAL;
+ if (fwspec->param[0] < 16) {
+ pr_err(FW_BUG "Illegal GSI%d translation request\n",
+ fwspec->param[0]);
+ return -EINVAL;
+ }
+
*hwirq = fwspec->param[0];
*type = fwspec->param[1];
diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index 58ba835bee1f..09c710ecc387 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -1123,6 +1123,12 @@ static int gic_irq_domain_translate(struct irq_domain *d,
if(fwspec->param_count != 2)
return -EINVAL;
+ if (fwspec->param[0] < 16) {
+ pr_err(FW_BUG "Illegal GSI%d translation request\n",
+ fwspec->param[0]);
+ return -EINVAL;
+ }
+
*hwirq = fwspec->param[0];
*type = fwspec->param[1];
--
2.31.1