Commit a1558727 authored by Anup Patel's avatar Anup Patel Committed by Thomas Gleixner
Browse files

irqchip/sifive-plic: Cleanup PLIC contexts upon irqdomain creation failure 



The SiFive PLIC contexts should not be left dangling if irqdomain creation
fails because plic_starting_cpu() can crash accessing unmapped registers.

Signed-off-by: default avatarAnup Patel <apatel@ventanamicro.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240222094006.1030709-6-apatel@ventanamicro.com
parent 6c725f33

drivers/irqchip/irq-sifive-plic.c

+53 −20
Original line number Diff line number Diff line
@@ -417,17 +417,45 @@ static const struct of_device_id plic_match[] = { 
	{}

};



static int plic_parse_context_parent(struct platform_device *pdev, u32 context,

				     u32 *parent_hwirq, int *parent_cpu)

{

	struct device *dev = &pdev->dev;

	struct of_phandle_args parent;

	unsigned long hartid;

	int rc;



	/*

	 * Currently, only OF fwnode is supported so extend this

	 * function for ACPI support.

	 */

	if (!is_of_node(dev->fwnode))

		return -EINVAL;



	rc = of_irq_parse_one(to_of_node(dev->fwnode), context, &parent);

	if (rc)

		return rc;



	rc = riscv_of_parent_hartid(parent.np, &hartid);

	if (rc)

		return rc;



	*parent_hwirq = parent.args[0];

	*parent_cpu = riscv_hartid_to_cpuid(hartid);

	return 0;

}



static int plic_probe(struct platform_device *pdev)

{

	int error = 0, nr_contexts, nr_handlers = 0, i;

	int error = 0, nr_contexts, nr_handlers = 0, cpu, i;

	struct device *dev = &pdev->dev;

	unsigned long plic_quirks = 0;

	struct plic_handler *handler;

	u32 nr_irqs, parent_hwirq;

	struct irq_domain *domain;

	struct plic_priv *priv;

	irq_hw_number_t hwirq;

	bool cpuhp_setup;

	unsigned int cpu;

	u32 nr_irqs;



	if (is_of_node(dev->fwnode)) {

		const struct of_device_id *id;
@@ -463,13 +491,9 @@ static int plic_probe(struct platform_device *pdev) 
		return -EINVAL;



	for (i = 0; i < nr_contexts; i++) {

		struct of_phandle_args parent;

		irq_hw_number_t hwirq;

		int cpu;

		unsigned long hartid;



		if (of_irq_parse_one(to_of_node(dev->fwnode), i, &parent)) {

			dev_err(dev, "failed to parse parent for context %d.\n", i);

		error = plic_parse_context_parent(pdev, i, &parent_hwirq, &cpu);

		if (error) {

			dev_warn(dev, "hwirq for context%d not found\n", i);

			continue;

		}
@@ -477,7 +501,7 @@ static int plic_probe(struct platform_device *pdev) 
		 * Skip contexts other than external interrupts for our

		 * privilege level.

		 */

		if (parent.args[0] != RV_IRQ_EXT) {

		if (parent_hwirq != RV_IRQ_EXT) {

			/* Disable S-mode enable bits if running in M-mode. */

			if (IS_ENABLED(CONFIG_RISCV_M_MODE)) {

				void __iomem *enable_base = priv->regs +
@@ -490,13 +514,6 @@ static int plic_probe(struct platform_device *pdev) 
			continue;

		}



		error = riscv_of_parent_hartid(parent.np, &hartid);

		if (error < 0) {

			dev_warn(dev, "failed to parse hart ID for context %d.\n", i);

			continue;

		}



		cpu = riscv_hartid_to_cpuid(hartid);

		if (cpu < 0) {

			dev_warn(dev, "Invalid cpuid for context %d\n", i);

			continue;
@@ -534,7 +551,7 @@ static int plic_probe(struct platform_device *pdev) 
		handler->enable_save = devm_kcalloc(dev, DIV_ROUND_UP(nr_irqs, 32),

						    sizeof(*handler->enable_save), GFP_KERNEL);

		if (!handler->enable_save)

			return -ENOMEM;

			goto fail_cleanup_contexts;

done:

		for (hwirq = 1; hwirq <= nr_irqs; hwirq++) {

			plic_toggle(handler, hwirq, 0);
@@ -547,7 +564,7 @@ static int plic_probe(struct platform_device *pdev) 
	priv->irqdomain = irq_domain_add_linear(to_of_node(dev->fwnode), nr_irqs + 1,

						&plic_irqdomain_ops, priv);

	if (WARN_ON(!priv->irqdomain))

		return -ENOMEM;

		goto fail_cleanup_contexts;



	/*

	 * We can have multiple PLIC instances so setup cpuhp state
@@ -575,6 +592,22 @@ static int plic_probe(struct platform_device *pdev) 
	dev_info(dev, "mapped %d interrupts with %d handlers for %d contexts.\n",

		 nr_irqs, nr_handlers, nr_contexts);

	return 0;



fail_cleanup_contexts:

	for (i = 0; i < nr_contexts; i++) {

		if (plic_parse_context_parent(pdev, i, &parent_hwirq, &cpu))

			continue;

		if (parent_hwirq != RV_IRQ_EXT || cpu < 0)

			continue;



		handler = per_cpu_ptr(&plic_handlers, cpu);

		handler->present = false;

		handler->hart_base = NULL;

		handler->enable_base = NULL;

		handler->enable_save = NULL;

		handler->priv = NULL;

	}

	return -ENOMEM;

}



static struct platform_driver plic_driver = {