Simpler to reason about and avoids having to free nodes separately.

Also add __counted_by attribute for extra runtime analysis.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/mtd/mtd_virt_concat.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/drivers/mtd/mtd_virt_concat.c b/drivers/mtd/mtd_virt_concat.c
index aea88d1c9bc5..89e223edac6a 100644
--- a/drivers/mtd/mtd_virt_concat.c
+++ b/drivers/mtd/mtd_virt_concat.c
@@ -31,8 +31,8 @@ static LIST_HEAD(concat_node_list);
 struct mtd_virt_concat_node {
 	struct list_head head;
 	unsigned int count;
-	struct device_node **nodes;
 	struct mtd_concat *concat;
+	struct device_node *nodes[] __counted_by(nodes);
 };
 
 /**
@@ -133,7 +133,6 @@ int mtd_virt_concat_destroy(struct mtd_info *mtd)
 		for (idx = 0; idx < item->count; idx++)
 			of_node_put(item->nodes[idx]);
 
-		kfree(item->nodes);
 		kfree(item);
 	}
 	return 0;
@@ -167,16 +166,11 @@ static int mtd_virt_concat_create_item(struct device_node *parts,
 			return 0;
 	}
 
-	item = kzalloc(sizeof(*item), GFP_KERNEL);
+	item = kzalloc_flex(*item, nodes, count, GFP_KERNEL);
 	if (!item)
 		return -ENOMEM;
 
 	item->count = count;
-	item->nodes = kcalloc(count, sizeof(*item->nodes), GFP_KERNEL);
-	if (!item->nodes) {
-		kfree(item);
-		return -ENOMEM;
-	}
 
 	/*
 	 * The partition in which "part-concat-next" property
@@ -216,7 +210,6 @@ void mtd_virt_concat_destroy_items(void)
 		for (i = 0; i < item->count; i++)
 			of_node_put(item->nodes[i]);
 
-		kfree(item->nodes);
 		kfree(item);
 	}
 }
-- 
2.53.0

Hello,

Am Wed, Mar 04, 2026 at 02:15:29PM -0800 schrieb Rosen Penev:
> Also add __counted_by attribute for extra runtime analysis.
…
> diff --git a/drivers/mtd/mtd_virt_concat.c b/drivers/mtd/mtd_virt_concat.c
> index aea88d1c9bc5..89e223edac6a 100644
> --- a/drivers/mtd/mtd_virt_concat.c
> +++ b/drivers/mtd/mtd_virt_concat.c
> @@ -31,8 +31,8 @@ static LIST_HEAD(concat_node_list);
>  struct mtd_virt_concat_node {
>  	struct list_head head;
>  	unsigned int count;
> -	struct device_node **nodes;
>  	struct mtd_concat *concat;
> +	struct device_node *nodes[] __counted_by(nodes);

Looks wrong. Your follow-up patch does that:
-       struct device_node *nodes[] __counted_by(nodes);
+       struct device_node *nodes[] __counted_by(count);

Philipp

On Wed, Mar 4, 2026 at 11:08 PM Philipp Matthias Hahn <pmhahn@pmhahn.de> wrote:
>
> Hello,
>
> Am Wed, Mar 04, 2026 at 02:15:29PM -0800 schrieb Rosen Penev:
> > Also add __counted_by attribute for extra runtime analysis.
> …
> > diff --git a/drivers/mtd/mtd_virt_concat.c b/drivers/mtd/mtd_virt_concat.c
> > index aea88d1c9bc5..89e223edac6a 100644
> > --- a/drivers/mtd/mtd_virt_concat.c
> > +++ b/drivers/mtd/mtd_virt_concat.c
> > @@ -31,8 +31,8 @@ static LIST_HEAD(concat_node_list);
> >  struct mtd_virt_concat_node {
> >       struct list_head head;
> >       unsigned int count;
> > -     struct device_node **nodes;
> >       struct mtd_concat *concat;
> > +     struct device_node *nodes[] __counted_by(nodes);
>
> Looks wrong. Your follow-up patch does that:
> -       struct device_node *nodes[] __counted_by(nodes);
> +       struct device_node *nodes[] __counted_by(count);
D'oh. I'll resend in a day.
>
> Philipp