This is a note to let you know that I've just added the patch titled irqdomain: Fix mapping-creation race to the 5.15-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-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 601363cc08da25747feb87c55573dd54de91d66a Mon Sep 17 00:00:00 2001 From: Johan Hovold <johan+linaro@xxxxxxxxxx> Date: Mon, 13 Feb 2023 11:42:48 +0100 Subject: irqdomain: Fix mapping-creation race From: Johan Hovold <johan+linaro@xxxxxxxxxx> commit 601363cc08da25747feb87c55573dd54de91d66a upstream. 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@xxxxxxxxxxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx # 4.8 Cc: Dmitry Torokhov <dtor@xxxxxxxxxxxx> Cc: Jon Hunter <jonathanh@xxxxxxxxxx> Tested-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx> Tested-by: Mark-PK Tsai <mark-pk.tsai@xxxxxxxxxxxx> Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx> Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230213104302.17307-7-johan+linaro@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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 { @@ -703,9 +706,9 @@ unsigned int irq_create_direct_mapping(s EXPORT_SYMBOL_GPL(irq_create_direct_mapping); #endif -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; @@ -720,7 +723,7 @@ 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; } @@ -756,14 +759,20 @@ 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); @@ -830,6 +839,8 @@ 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. @@ -842,7 +853,7 @@ 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 @@ -850,35 +861,45 @@ 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; } @@ -1902,6 +1923,13 @@ 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 johan+linaro@xxxxxxxxxx are queue-5.15/irqdomain-fix-mapping-creation-race.patch