On Sat, 11 Nov 2017 17:51:25 +0100
Johan Hovold <johan@xxxxxxxxxx> wrote:
Johan,
> Fix child-node lookup during initialisation, which ended up searching
> the whole device tree depth-first starting at the parent rather than
> just matching on its children.
>
> To make things worse, the parent giq node was prematurely freed, while
s/giq/gic/.
Care to point out where that node would be prematurely freed? I don't
see your patch addressing that either...
> the ppi-partitions node was leaked.
>
> Fixes: e3825ba1af3a ("irqchip/gic-v3: Add support for partitioned PPIs")
> Cc: stable <stable@xxxxxxxxxxxxxxx> # 4.7
Do you have an example of this causing any trouble in the wild? As far
as I remember, the whole of_node refcounting isn't really enforced, so
while this is definitely a bug, it wouldn't cause any harm anywhere.
Or am I missing something obvious?
Thanks,
M.
> Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
> ---
> drivers/irqchip/irq-gic-v3.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
> index 17221143f505..af1f8373d8bf 100644
> --- a/drivers/irqchip/irq-gic-v3.c
> +++ b/drivers/irqchip/irq-gic-v3.c
> @@ -1103,18 +1103,18 @@ static void __init gic_populate_ppi_partitions(struct device_node *gic_node)
> int nr_parts;
> struct partition_affinity *parts;
>
> - parts_node = of_find_node_by_name(gic_node, "ppi-partitions");
> + parts_node = of_get_child_by_name(gic_node, "ppi-partitions");
> if (!parts_node)
> return;
>
> nr_parts = of_get_child_count(parts_node);
>
> if (!nr_parts)
> - return;
> + goto out_put_node;
>
> parts = kzalloc(sizeof(*parts) * nr_parts, GFP_KERNEL);
> if (WARN_ON(!parts))
> - return;
> + goto out_put_node;
>
> for_each_child_of_node(parts_node, child_part) {
> struct partition_affinity *part;
> @@ -1181,6 +1181,9 @@ static void __init gic_populate_ppi_partitions(struct device_node *gic_node)
>
> gic_data.ppi_descs[i] = desc;
> }
> +
> +out_put_node:
> + of_node_put(parts_node);
> }
>
> static void __init gic_of_setup_kvm_info(struct device_node *node)
--
Without deviation from the norm, progress is not possible.