Patch "irqdomain: Fix mapping-creation race" has been added to the 5.4-stable tree

gregkh
2023-04-11T14:19:52Z

This is a note to let you know that I've just added the patch titled

irqdomain: Fix mapping-creation race

to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
irqdomain-fix-mapping-creation-race.patch
and it can be found in the queue-5.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.

From stable-owner@vger.kernel.org Wed Mar 22 13:46:07 2023
From: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Date: Wed, 22 Mar 2023 20:45:50 +0800
Subject: irqdomain: Fix mapping-creation race
To: Marc Zyngier <maz@kernel.org>, Thomas Gleixner <tglx@linutronix.de>, Matthias Brugger <matthias.bgg@gmail.com>
Cc: Johan Hovold <johan+linaro@kernel.org>, <stable@vger.kernel.org>, Dmitry Torokhov <dtor@chromium.org>, Jon Hunter <jonathanh@nvidia.com>, Sasha Levin <sashal@kernel.org>, Mark-PK Tsai <mark-pk.tsai@mediatek.com>, <linux-kernel@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>, <linux-mediatek@lists.infradead.org>
Message-ID: <20230322124550.29812-3-mark-pk.tsai@mediatek.com>

From: Johan Hovold <johan+linaro@kernel.org>

[ Upstream commit 601363cc08da25747feb87c55573dd54de91d66a ]

Parallel probing of devices that share interrupts (e.g. when a driver
uses asynchronous probing) can currently result in two mappings for the
same hardware interrupt to be created due to missing serialisation.

Make sure to hold the irq_domain_mutex when creating mappings so that
looking for an existing mapping before creating a new one is done
atomically.

Fixes: 765230b5f084 ("driver-core: add asynchronous probing support for drivers")
Fixes: b62b2cf5759b ("irqdomain: Fix handling of type settings for existing mappings")
Link: https://lore.kernel.org/r/YuJXMHoT4ijUxnRb@hovoldconsulting.com
Cc: stable@vger.kernel.org # 4.8
Cc: Dmitry Torokhov <dtor@chromium.org>
Cc: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Hsin-Yi Wang <hsinyi@chromium.org>
Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230213104302.17307-7-johan+linaro@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
kernel/irq/irqdomain.c | 64 +++++++++++++++++++++++++++++++++++--------------
1 file changed, 46 insertions(+), 18 deletions(-)

--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -25,6 +25,9 @@ static DEFINE_MUTEX(irq_domain_mutex);

static struct irq_domain *irq_default_domain;

+static int irq_domain_alloc_irqs_locked(struct irq_domain *domain, int irq_base,
+ unsigned int nr_irqs, int node, void *arg,
+ bool realloc, const struct irq_affinity_desc *affinity);
static void irq_domain_check_hierarchy(struct irq_domain *domain);

struct irqchip_fwid {
@@ -672,9 +675,9 @@ unsigned int irq_create_direct_mapping(s
}
EXPORT_SYMBOL_GPL(irq_create_direct_mapping);

-static unsigned int __irq_create_mapping_affinity(struct irq_domain *domain,
- irq_hw_number_t hwirq,
- const struct irq_affinity_desc *affinity)
+static unsigned int irq_create_mapping_affinity_locked(struct irq_domain *domain,
+ irq_hw_number_t hwirq,
+ const struct irq_affinity_desc *affinity)
{
struct device_node *of_node = irq_domain_get_of_node(domain);
int virq;
@@ -689,7 +692,7 @@ static unsigned int __irq_create_mapping
return 0;
}

- if (irq_domain_associate(domain, virq, hwirq)) {
+ if (irq_domain_associate_locked(domain, virq, hwirq)) {
irq_free_desc(virq);
return 0;
}
@@ -725,14 +728,20 @@ unsigned int irq_create_mapping_affinity
return 0;
}

+ mutex_lock(&irq_domain_mutex);
+
/* Check if mapping already exists */
virq = irq_find_mapping(domain, hwirq);
if (virq) {
pr_debug("existing mapping on virq %d\n", virq);
- return virq;
+ goto out;
}

- return __irq_create_mapping_affinity(domain, hwirq, affinity);
+ virq = irq_create_mapping_affinity_locked(domain, hwirq, affinity);
+out:
+ mutex_unlock(&irq_domain_mutex);
+
+ return virq;
}
EXPORT_SYMBOL_GPL(irq_create_mapping_affinity);

@@ -834,6 +843,8 @@ unsigned int irq_create_fwspec_mapping(s
if (WARN_ON(type & ~IRQ_TYPE_SENSE_MASK))
type &= IRQ_TYPE_SENSE_MASK;

+ mutex_lock(&irq_domain_mutex);
+
/*
* If we've already configured this interrupt,
* don't do it again, or hell will break loose.
@@ -846,7 +857,7 @@ unsigned int irq_create_fwspec_mapping(s
* interrupt number.
*/
if (type == IRQ_TYPE_NONE || type == irq_get_trigger_type(virq))
- return virq;
+ goto out;

/*
* If the trigger type has not been set yet, then set
@@ -854,35 +865,45 @@ unsigned int irq_create_fwspec_mapping(s
*/
if (irq_get_trigger_type(virq) == IRQ_TYPE_NONE) {
irq_data = irq_get_irq_data(virq);
- if (!irq_data)
- return 0;
+ if (!irq_data) {
+ virq = 0;
+ goto out;
+ }

irqd_set_trigger_type(irq_data, type);
- return virq;
+ goto out;
}

pr_warn("type mismatch, failed to map hwirq-%lu for %s!\n",
hwirq, of_node_full_name(to_of_node(fwspec->fwnode)));
- return 0;
+ virq = 0;
+ goto out;
}

if (irq_domain_is_hierarchy(domain)) {
- virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, fwspec);
- if (virq <= 0)
- return 0;
+ virq = irq_domain_alloc_irqs_locked(domain, -1, 1, NUMA_NO_NODE,
+ fwspec, false, NULL);
+ if (virq <= 0) {
+ virq = 0;
+ goto out;
+ }
} else {
/* Create mapping */
- virq = __irq_create_mapping_affinity(domain, hwirq, NULL);
+ virq = irq_create_mapping_affinity_locked(domain, hwirq, NULL);
if (!virq)
- return virq;
+ goto out;
}

irq_data = irq_get_irq_data(virq);
- if (WARN_ON(!irq_data))
- return 0;
+ if (WARN_ON(!irq_data)) {
+ virq = 0;
+ goto out;
+ }

/* Store trigger type */
irqd_set_trigger_type(irq_data, type);
+out:
+ mutex_unlock(&irq_domain_mutex);

return virq;
}
@@ -1788,6 +1809,13 @@ void irq_domain_set_info(struct irq_doma
irq_set_handler_data(virq, handler_data);
}

+static int irq_domain_alloc_irqs_locked(struct irq_domain *domain, int irq_base,
+ unsigned int nr_irqs, int node, void *arg,
+ bool realloc, const struct irq_affinity_desc *affinity)
+{
+ return -EINVAL;
+}
+
static void irq_domain_check_hierarchy(struct irq_domain *domain)
{
}

Patches currently in stable-queue which might be from stable-owner@vger.kernel.org are

queue-5.4/irqdomain-fix-mapping-creation-race.patch
queue-5.4/irqdomain-refactor-__irq_domain_alloc_irqs.patch
queue-5.4/irqdomain-look-for-existing-mapping-only-once.patch