Re: [PATCH 1/1] arm: devtree: fix missing device_node cleanup

[vincenzo mezzela]

On 7/12/24 11:47, Javier Carrasco wrote:
> On 12/07/2024 11:44, Vincenzo Mezzela wrote:
> > Device node `cpus` is allocated but never released using `of_node_put`.
> >
> > This patch introduces the __free attribute for `cpus` device_node that
> > automatically handle the cleanup of the resource by adding a call to
> > `of_node_put` at the end of the current scope. This enhancement aims to
> > mitigate memory management issues associated with forgetting to release
> > the resources.
> >
> > Signed-off-by: Vincenzo Mezzela <vincenzo.mezzela@xxxxxxxxx>
> > ---
> >   arch/arm/kernel/devtree.c | 4 ++--
> >   1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c
> > index fdb74e64206a..223d66a5fff3 100644
> > --- a/arch/arm/kernel/devtree.c
> > +++ b/arch/arm/kernel/devtree.c
> > @@ -70,14 +70,14 @@ void __init arm_dt_init_cpu_maps(void)
> >   	 * contain a list of MPIDR[23:0] values where MPIDR[31:24] must
> >   	 * read as 0.
> >   	 */
> > -	struct device_node *cpu, *cpus;
> >   	int found_method = 0;
> >   	u32 i, j, cpuidx = 1;
> >   	u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0;
> >   
> >   	u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID };
> >   	bool bootcpu_valid = false;
> > -	cpus = of_find_node_by_path("/cpus");
> > +	struct device_node *cpu;
> > +	struct device_node *cpus __free(device_node) = of_find_node_by_path("/cpus");
> >   
> >   	if (!cpus)
> >   		return;
> Hello Vincenzo,
>
> If this is a fix, please provide the Fixes: tag as well as Cc: for
> stable if it applies.
>
> Best regards, Javier Carrasco

Sure, will do. :)


Best regards,

Vincenzo


Fixes: a0ae02405076a ("ARM: kernel: add device tree init map function")
Cc: stable@xxxxxxxxxxxxxxx