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authorMarc Zyngier <marc.zyngier@arm.com>2017-01-17 16:00:48 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-02-09 08:08:31 +0100
commite02136282296dbc90f3c88b1cc5202ec0d5ed9f1 (patch)
tree19b9130ef7ee0fc56a72726e4a0e412b98c49553 /kernel
parentc6b0333baea0acbe792c22ac71a04e40e26a8398 (diff)
irqdomain: Avoid activating interrupts more than once
commit 08d85f3ea99f1eeafc4e8507936190e86a16ee8c upstream. Since commit f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early"), we can end-up activating a PCI/MSI twice (once at allocation time, and once at startup time). This is normally of no consequences, except that there is some HW out there that may misbehave if activate is used more than once (the GICv3 ITS, for example, uses the activate callback to issue the MAPVI command, and the architecture spec says that "If there is an existing mapping for the EventID-DeviceID combination, behavior is UNPREDICTABLE"). While this could be worked around in each individual driver, it may make more sense to tackle the issue at the core level. In order to avoid getting in that situation, let's have a per-interrupt flag to remember if we have already activated that interrupt or not. Fixes: f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early") Reported-and-tested-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Link: http://lkml.kernel.org/r/1484668848-24361-1-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/irq/irqdomain.c44
1 files changed, 30 insertions, 14 deletions
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 8c0a0ae43521..b59e6768c5e9 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1346,6 +1346,30 @@ void irq_domain_free_irqs_parent(struct irq_domain *domain,
}
EXPORT_SYMBOL_GPL(irq_domain_free_irqs_parent);
+static void __irq_domain_activate_irq(struct irq_data *irq_data)
+{
+ if (irq_data && irq_data->domain) {
+ struct irq_domain *domain = irq_data->domain;
+
+ if (irq_data->parent_data)
+ __irq_domain_activate_irq(irq_data->parent_data);
+ if (domain->ops->activate)
+ domain->ops->activate(domain, irq_data);
+ }
+}
+
+static void __irq_domain_deactivate_irq(struct irq_data *irq_data)
+{
+ if (irq_data && irq_data->domain) {
+ struct irq_domain *domain = irq_data->domain;
+
+ if (domain->ops->deactivate)
+ domain->ops->deactivate(domain, irq_data);
+ if (irq_data->parent_data)
+ __irq_domain_deactivate_irq(irq_data->parent_data);
+ }
+}
+
/**
* irq_domain_activate_irq - Call domain_ops->activate recursively to activate
* interrupt
@@ -1356,13 +1380,9 @@ EXPORT_SYMBOL_GPL(irq_domain_free_irqs_parent);
*/
void irq_domain_activate_irq(struct irq_data *irq_data)
{
- if (irq_data && irq_data->domain) {
- struct irq_domain *domain = irq_data->domain;
-
- if (irq_data->parent_data)
- irq_domain_activate_irq(irq_data->parent_data);
- if (domain->ops->activate)
- domain->ops->activate(domain, irq_data);
+ if (!irqd_is_activated(irq_data)) {
+ __irq_domain_activate_irq(irq_data);
+ irqd_set_activated(irq_data);
}
}
@@ -1376,13 +1396,9 @@ void irq_domain_activate_irq(struct irq_data *irq_data)
*/
void irq_domain_deactivate_irq(struct irq_data *irq_data)
{
- if (irq_data && irq_data->domain) {
- struct irq_domain *domain = irq_data->domain;
-
- if (domain->ops->deactivate)
- domain->ops->deactivate(domain, irq_data);
- if (irq_data->parent_data)
- irq_domain_deactivate_irq(irq_data->parent_data);
+ if (irqd_is_activated(irq_data)) {
+ __irq_domain_deactivate_irq(irq_data);
+ irqd_clr_activated(irq_data);
}
}