Refactor __irq_domain_alloc_irqs() so that it can be called internally
while holding the irq_domain_mutex.
This will be used to fix a shared-interrupt mapping race, hence the
Fixes tag.
Fixes: b62b2cf5759b ("irqdomain: Fix handling of type settings for existing mappings")
Cc: stable(a)vger.kernel.org # 4.8
Tested-by: Hsin-Yi Wang <hsinyi(a)chromium.org>
Tested-by: Mark-PK Tsai <mark-pk.tsai(a)mediatek.com>
Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org>
---
kernel/irq/irqdomain.c | 88 +++++++++++++++++++++++-------------------
1 file changed, 48 insertions(+), 40 deletions(-)
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 3d6a14efae62..7b57949bc79c 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1441,40 +1441,12 @@ int irq_domain_alloc_irqs_hierarchy(struct irq_domain *domain,
return domain->ops->alloc(domain, irq_base, nr_irqs, arg);
}
-/**
- * __irq_domain_alloc_irqs - Allocate IRQs from domain
- * @domain: domain to allocate from
- * @irq_base: allocate specified IRQ number if irq_base >= 0
- * @nr_irqs: number of IRQs to allocate
- * @node: NUMA node id for memory allocation
- * @arg: domain specific argument
- * @realloc: IRQ descriptors have already been allocated if true
- * @affinity: Optional irq affinity mask for multiqueue devices
- *
- * Allocate IRQ numbers and initialized all data structures to support
- * hierarchy IRQ domains.
- * Parameter @realloc is mainly to support legacy IRQs.
- * Returns error code or allocated IRQ number
- *
- * The whole process to setup an IRQ has been split into two steps.
- * The first step, __irq_domain_alloc_irqs(), is to allocate IRQ
- * descriptor and required hardware resources. The second step,
- * irq_domain_activate_irq(), is to program the hardware with preallocated
- * resources. In this way, it's easier to rollback when failing to
- * allocate resources.
- */
-int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
- unsigned int nr_irqs, int node, void *arg,
- bool realloc, const struct irq_affinity_desc *affinity)
+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)
{
int i, ret, virq;
- if (domain == NULL) {
- domain = irq_default_domain;
- if (WARN(!domain, "domain is NULL; cannot allocate IRQ\n"))
- return -EINVAL;
- }
-
if (realloc && irq_base >= 0) {
virq = irq_base;
} else {
@@ -1493,24 +1465,18 @@ int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
goto out_free_desc;
}
- mutex_lock(&irq_domain_mutex);
ret = irq_domain_alloc_irqs_hierarchy(domain, virq, nr_irqs, arg);
- if (ret < 0) {
- mutex_unlock(&irq_domain_mutex);
+ if (ret < 0)
goto out_free_irq_data;
- }
for (i = 0; i < nr_irqs; i++) {
ret = irq_domain_trim_hierarchy(virq + i);
- if (ret) {
- mutex_unlock(&irq_domain_mutex);
+ if (ret)
goto out_free_irq_data;
- }
}
-
+
for (i = 0; i < nr_irqs; i++)
irq_domain_insert_irq(virq + i);
- mutex_unlock(&irq_domain_mutex);
return virq;
@@ -1520,6 +1486,48 @@ int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
irq_free_descs(virq, nr_irqs);
return ret;
}
+
+/**
+ * __irq_domain_alloc_irqs - Allocate IRQs from domain
+ * @domain: domain to allocate from
+ * @irq_base: allocate specified IRQ number if irq_base >= 0
+ * @nr_irqs: number of IRQs to allocate
+ * @node: NUMA node id for memory allocation
+ * @arg: domain specific argument
+ * @realloc: IRQ descriptors have already been allocated if true
+ * @affinity: Optional irq affinity mask for multiqueue devices
+ *
+ * Allocate IRQ numbers and initialized all data structures to support
+ * hierarchy IRQ domains.
+ * Parameter @realloc is mainly to support legacy IRQs.
+ * Returns error code or allocated IRQ number
+ *
+ * The whole process to setup an IRQ has been split into two steps.
+ * The first step, __irq_domain_alloc_irqs(), is to allocate IRQ
+ * descriptor and required hardware resources. The second step,
+ * irq_domain_activate_irq(), is to program the hardware with preallocated
+ * resources. In this way, it's easier to rollback when failing to
+ * allocate resources.
+ */
+int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
+ unsigned int nr_irqs, int node, void *arg,
+ bool realloc, const struct irq_affinity_desc *affinity)
+{
+ int ret;
+
+ if (domain == NULL) {
+ domain = irq_default_domain;
+ if (WARN(!domain, "domain is NULL; cannot allocate IRQ\n"))
+ return -EINVAL;
+ }
+
+ mutex_lock(&irq_domain_mutex);
+ ret = irq_domain_alloc_irqs_locked(domain, irq_base, nr_irqs, node, arg,
+ realloc, affinity);
+ mutex_unlock(&irq_domain_mutex);
+
+ return ret;
+}
EXPORT_SYMBOL_GPL(__irq_domain_alloc_irqs);
/* The irq_data was moved, fix the revmap to refer to the new location */
--
2.39.1
In case a newly allocated IRQ ever ends up not having any associated
struct irq_data it would not even be possible to dispose the mapping.
Replace the bogus disposal with a WARN_ON().
This will also be used to fix a shared-interrupt mapping race, hence the
CC-stable tag.
Fixes: 1e2a7d78499e ("irqdomain: Don't set type when mapping an IRQ")
Cc: stable(a)vger.kernel.org # 4.8
Tested-by: Hsin-Yi Wang <hsinyi(a)chromium.org>
Tested-by: Mark-PK Tsai <mark-pk.tsai(a)mediatek.com>
Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org>
---
kernel/irq/irqdomain.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 981cd636275e..b4326c364ae7 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -847,13 +847,8 @@ unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec)
}
irq_data = irq_get_irq_data(virq);
- if (!irq_data) {
- if (irq_domain_is_hierarchy(domain))
- irq_domain_free_irqs(virq, 1);
- else
- irq_dispose_mapping(virq);
+ if (WARN_ON(!irq_data))
return 0;
- }
/* Store trigger type */
irqd_set_trigger_type(irq_data, type);
--
2.39.1
The global irq_domain_mutex is held when mapping interrupts from
non-hierarchical domains but currently not when disposing them.
This specifically means that updates of the domain mapcount is racy
(currently only used for statistics in debugfs).
Make sure to hold the global irq_domain_mutex also when disposing
mappings from non-hierarchical domains.
Fixes: 9dc6be3d4193 ("genirq/irqdomain: Add map counter")
Cc: stable(a)vger.kernel.org # 4.13
Tested-by: Hsin-Yi Wang <hsinyi(a)chromium.org>
Tested-by: Mark-PK Tsai <mark-pk.tsai(a)mediatek.com>
Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org>
---
kernel/irq/irqdomain.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 561689a3f050..981cd636275e 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -538,6 +538,9 @@ static void irq_domain_disassociate(struct irq_domain *domain, unsigned int irq)
return;
hwirq = irq_data->hwirq;
+
+ mutex_lock(&irq_domain_mutex);
+
irq_set_status_flags(irq, IRQ_NOREQUEST);
/* remove chip and handler */
@@ -557,6 +560,8 @@ static void irq_domain_disassociate(struct irq_domain *domain, unsigned int irq)
/* Clear reverse map for this hwirq */
irq_domain_clear_mapping(domain, hwirq);
+
+ mutex_unlock(&irq_domain_mutex);
}
static int irq_domain_associate_locked(struct irq_domain *domain, unsigned int virq,
--
2.39.1