This is a note to let you know that I've just added the patch titled irqchip/riscv-intc: Allow large non-standard interrupt number to the 6.6-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: irqchip-riscv-intc-allow-large-non-standard-interrup.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit eed7836bce48533294afc37ef0c2453a6e9384b1 Author: Yu Chien Peter Lin <peterlin@xxxxxxxxxxxxx> Date: Thu Feb 22 16:39:38 2024 +0800 irqchip/riscv-intc: Allow large non-standard interrupt number [ Upstream commit 96303bcb401c21dc1426d8d9bb1fc74aae5c02a9 ] Currently, the implementation of the RISC-V INTC driver uses the interrupt cause as the hardware interrupt number, with a maximum of 64 interrupts. However, the platform can expand the interrupt number further for custom local interrupts. To fully utilize the available local interrupt sources, switch to using irq_domain_create_tree() that creates the radix tree map, add global variables (riscv_intc_nr_irqs, riscv_intc_custom_base and riscv_intc_custom_nr_irqs) to determine the valid range of local interrupt number (hwirq). Signed-off-by: Yu Chien Peter Lin <peterlin@xxxxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Reviewed-by: Randolph <randolph@xxxxxxxxxxxxx> Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx> Reviewed-by: Atish Patra <atishp@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20240222083946.3977135-3-peterlin@xxxxxxxxxxxxx Stable-dep-of: 0110c4b11047 ("irqchip/riscv-intc: Prevent memory leak when riscv_intc_init_common() fails") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/irqchip/irq-riscv-intc.c b/drivers/irqchip/irq-riscv-intc.c index e8d01b14ccdde..684875c397280 100644 --- a/drivers/irqchip/irq-riscv-intc.c +++ b/drivers/irqchip/irq-riscv-intc.c @@ -19,15 +19,16 @@ #include <linux/smp.h> static struct irq_domain *intc_domain; +static unsigned int riscv_intc_nr_irqs __ro_after_init = BITS_PER_LONG; +static unsigned int riscv_intc_custom_base __ro_after_init = BITS_PER_LONG; +static unsigned int riscv_intc_custom_nr_irqs __ro_after_init; static asmlinkage void riscv_intc_irq(struct pt_regs *regs) { unsigned long cause = regs->cause & ~CAUSE_IRQ_FLAG; - if (unlikely(cause >= BITS_PER_LONG)) - panic("unexpected interrupt cause"); - - generic_handle_domain_irq(intc_domain, cause); + if (generic_handle_domain_irq(intc_domain, cause)) + pr_warn_ratelimited("Failed to handle interrupt (cause: %ld)\n", cause); } /* @@ -93,6 +94,14 @@ static int riscv_intc_domain_alloc(struct irq_domain *domain, if (ret) return ret; + /* + * Only allow hwirq for which we have corresponding standard or + * custom interrupt enable register. + */ + if ((hwirq >= riscv_intc_nr_irqs && hwirq < riscv_intc_custom_base) || + (hwirq >= riscv_intc_custom_base + riscv_intc_custom_nr_irqs)) + return -EINVAL; + for (i = 0; i < nr_irqs; i++) { ret = riscv_intc_domain_map(domain, virq + i, hwirq + i); if (ret) @@ -117,8 +126,7 @@ static int __init riscv_intc_init_common(struct fwnode_handle *fn) { int rc; - intc_domain = irq_domain_create_linear(fn, BITS_PER_LONG, - &riscv_intc_domain_ops, NULL); + intc_domain = irq_domain_create_tree(fn, &riscv_intc_domain_ops, NULL); if (!intc_domain) { pr_err("unable to add IRQ domain\n"); return -ENXIO; @@ -132,7 +140,11 @@ static int __init riscv_intc_init_common(struct fwnode_handle *fn) riscv_set_intc_hwnode_fn(riscv_intc_hwnode); - pr_info("%d local interrupts mapped\n", BITS_PER_LONG); + pr_info("%d local interrupts mapped\n", riscv_intc_nr_irqs); + if (riscv_intc_custom_nr_irqs) { + pr_info("%d custom local interrupts mapped\n", + riscv_intc_custom_nr_irqs); + } return 0; }