Re: [PATCH v2] irqchip/gic-v3-its: Fix OF node reference leak

[Marc Zyngier]

On Fri, 26 Jun 2026 04:37:47 +0100,
Yuho Choi <dbgh9129@xxxxxxxxx> wrote:
> 
> of_get_cpu_node() returns a referenced device node. In
> its_cpu_init_collection(), the Cavium 23144 workaround only uses the
> node to compare the CPU NUMA node, but the reference is never dropped.
> 
> Use the device_node cleanup helper for the CPU node reference so it is
> released when leaving the workaround block, including the NUMA mismatch
> return path.
> 
> Fixes: fbf8f40e1658 ("irqchip/gicv3-its: numa: Enable workaround for Cavium thunderx erratum 23144")
> Signed-off-by: Yuho Choi <dbgh9129@xxxxxxxxx>
> ---
> - Use __free(device_node) for the CPU node reference.
> - Correct the Fixes tag to fbf8f40e1658.
> 
>  drivers/irqchip/irq-gic-v3-its.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index b57d81ad33a0..63942cf1dbe3 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -3290,9 +3290,9 @@ static void its_cpu_init_collection(struct its_node *its)
>  
>  	/* avoid cross node collections and its mapping */
>  	if (its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_23144) {
> -		struct device_node *cpu_node;
> +		struct device_node *cpu_node __free(device_node) =
> +			of_get_cpu_node(cpu, NULL);

Please keep this on a single line. I find nothing more irritating than
these split assignments.

>
> -		cpu_node = of_get_cpu_node(cpu, NULL);
>  		if (its->numa_node != NUMA_NO_NODE &&
>  			its->numa_node != of_node_to_nid(cpu_node))
>  			return;

Worth taking this opportunity to fix the indentation here.

With these two nits addressed:

Acked-by: Marc Zyngier <maz@xxxxxxxxxx>

	M.

-- 
Without deviation from the norm, progress is not possible.