The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x 6e6f75c9c98d2d246d90411ff2b6f0cd271f4cba # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '1678128480103128@kroah.com' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:

6e6f75c9c98d ("irqdomain: Look for existing mapping only once") a359f757965a ("irq: Fix typos in comments") bb4c6910c8b4 ("genirq/irqdomain: Add an irq_create_mapping_affinity() function") baedb87d1b53 ("genirq/affinity: Handle affinity setting on inactive interrupts correctly") ef8c01eb64ca ("irqchip: Add Loongson PCH PIC controller") 818e915fbac5 ("irqchip: Add Loongson HyperTransport Vector support") d71e064449a7 ("Merge tag 'mips_5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 6e6f75c9c98d2d246d90411ff2b6f0cd271f4cba Mon Sep 17 00:00:00 2001 From: Johan Hovold johan+linaro@kernel.org Date: Mon, 13 Feb 2023 11:42:46 +0100 Subject: [PATCH] irqdomain: Look for existing mapping only once

Avoid looking for an existing mapping twice when creating a new mapping using irq_create_fwspec_mapping() by factoring out the actual allocation which is shared with irq_create_mapping_affinity().

The new helper function will also 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@vger.kernel.org # 4.8 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/20230213104302.17307-5-johan+linaro@kernel.org

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 9f5b96cf6c5c..9f95047e4bc7 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -682,6 +682,34 @@ unsigned int irq_create_direct_mapping(struct irq_domain *domain) 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) +{ + struct device_node *of_node = irq_domain_get_of_node(domain); + int virq; + + pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq); + + /* Allocate a virtual interrupt number */ + virq = irq_domain_alloc_descs(-1, 1, hwirq, of_node_to_nid(of_node), + affinity); + if (virq <= 0) { + pr_debug("-> virq allocation failed\n"); + return 0; + } + + if (irq_domain_associate(domain, virq, hwirq)) { + irq_free_desc(virq); + return 0; + } + + pr_debug("irq %lu on domain %s mapped to virtual irq %u\n", + hwirq, of_node_full_name(of_node), virq); + + return virq; +} + /** * irq_create_mapping_affinity() - Map a hardware interrupt into linux irq space * @domain: domain owning this hardware interrupt or NULL for default domain @@ -694,14 +722,11 @@ EXPORT_SYMBOL_GPL(irq_create_direct_mapping); * on the number returned from that call. */ unsigned int irq_create_mapping_affinity(struct irq_domain *domain, - irq_hw_number_t hwirq, - const struct irq_affinity_desc *affinity) + irq_hw_number_t hwirq, + const struct irq_affinity_desc *affinity) { - struct device_node *of_node; int virq;

- pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq); - /* Look for default domain if necessary */ if (domain == NULL) domain = irq_default_domain; @@ -709,34 +734,15 @@ unsigned int irq_create_mapping_affinity(struct irq_domain *domain, WARN(1, "%s(, %lx) called with NULL domain\n", __func__, hwirq); return 0; } - pr_debug("-> using domain @%p\n", domain); - - of_node = irq_domain_get_of_node(domain);

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

- /* Allocate a virtual interrupt number */ - virq = irq_domain_alloc_descs(-1, 1, hwirq, of_node_to_nid(of_node), - affinity); - if (virq <= 0) { - pr_debug("-> virq allocation failed\n"); - return 0; - } - - if (irq_domain_associate(domain, virq, hwirq)) { - irq_free_desc(virq); - return 0; - } - - pr_debug("irq %lu on domain %s mapped to virtual irq %u\n", - hwirq, of_node_full_name(of_node), virq); - - return virq; + return __irq_create_mapping_affinity(domain, hwirq, affinity); } EXPORT_SYMBOL_GPL(irq_create_mapping_affinity);

@@ -841,7 +847,7 @@ unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec) return 0; } else { /* Create mapping */ - virq = irq_create_mapping(domain, hwirq); + virq = __irq_create_mapping_affinity(domain, hwirq, NULL); if (!virq) return virq; }