[PATCH] irqchip/riscv-intc: Fix no-SMP boot with ACPI

[Alexandre Ghiti]

Hi Thomas,

On 14/10/2024 08:57, Sunil V L wrote:
> When CONFIG_SMP is disabled, the static array rintc_acpi_data with size
> NR_CPUS will not be sufficient to hold all RINTC structures passed from
> the firmware. All RINTC structures are required to configure
> IMSIC/APLIC/PLIC properly irrespective of SMP in the OS. So, allocate
> dynamic memory based on the number of RINTC structures in MADT to fix
> this issue.
>
> Fixes: f8619b66bdb1 ("irqchip/riscv-intc: Add ACPI support for AIA")
> Reported-by: Björn Töpel <bjorn at kernel.org>
> Closes: https://github.com/linux-riscv/linux-riscv/actions/runs/11280997511/job/31375229012
> Signed-off-by: Sunil V L <sunilvl at ventanamicro.com>
> ---
>   drivers/irqchip/irq-riscv-intc.c | 19 ++++++++++++++++++-
>   1 file changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/irqchip/irq-riscv-intc.c b/drivers/irqchip/irq-riscv-intc.c
> index 8c5411386220..f653c13de62b 100644
> --- a/drivers/irqchip/irq-riscv-intc.c
> +++ b/drivers/irqchip/irq-riscv-intc.c
> @@ -265,7 +265,7 @@ struct rintc_data {
>   };
>   
>   static u32 nr_rintc;
> -static struct rintc_data *rintc_acpi_data[NR_CPUS];
> +static struct rintc_data **rintc_acpi_data;
>   
>   #define for_each_matching_plic(_plic_id)				\
>   	unsigned int _plic;						\
> @@ -329,13 +329,30 @@ int acpi_rintc_get_imsic_mmio_info(u32 index, struct resource *res)
>   	return 0;
>   }
>   
> +static int __init riscv_intc_acpi_match(union acpi_subtable_headers *header,
> +					const unsigned long end)
> +{
> +	return 0;
> +}
> +
>   static int __init riscv_intc_acpi_init(union acpi_subtable_headers *header,
>   				       const unsigned long end)
>   {
>   	struct acpi_madt_rintc *rintc;
>   	struct fwnode_handle *fn;
> +	int count;
>   	int rc;
>   
> +	if (!rintc_acpi_data) {
> +		count = acpi_table_parse_madt(ACPI_MADT_TYPE_RINTC, riscv_intc_acpi_match, 0);
> +		if (count <= 0)
> +			return -EINVAL;
> +
> +		rintc_acpi_data = kcalloc(count, sizeof(*rintc_acpi_data), GFP_KERNEL);
> +		if (!rintc_acpi_data)
> +			return -ENOMEM;
> +	}
> +
>   	rintc = (struct acpi_madt_rintc *)header;
>   	rintc_acpi_data[nr_rintc] = kzalloc(sizeof(*rintc_acpi_data[0]), GFP_KERNEL);
>   	if (!rintc_acpi_data[nr_rintc])


Do you think you can merge this patch for rc6? We still need it to fix 
our nosmp builds.

Thanks,

Alex