2013-06-23 07:50:17

by Axel Lin

Subject: [PATCH] of/irq: Avoid calling list_first_entry() for empty list

list_first_entry() expects the list is not empty, we need to check if list is
empty before calling list_first_entry(). Thus use list_first_entry_or_null()
instead of list_first_entry().

Signed-off-by: Axel Lin <[email protected]>
---
drivers/of/irq.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index a3c1c5a..5c645c7 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -482,8 +482,9 @@ void __init of_irq_init(const struct of_device_id *matches)
}

/* Get the next pending parent that might have children */
- desc = list_first_entry(&intc_parent_list, typeof(*desc), list);
- if (list_empty(&intc_parent_list) || !desc) {
+ desc = list_first_entry_or_null(&intc_parent_list,
+ typeof(*desc), list);
+ if (!desc) {
pr_err("of_irq_init: children remain, but no parents\n");
break;
}
--
1.8.1.2

2013-07-20 12:22:37

by Grant Likely

Subject: Re: [PATCH] of/irq: Avoid calling list_first_entry() for empty list

On Sun, 23 Jun 2013 15:50:07 +0800, Axel Lin <[email protected]> wrote:
> list_first_entry() expects the list is not empty, we need to check if list is
> empty before calling list_first_entry(). Thus use list_first_entry_or_null()
> instead of list_first_entry().
>
> Signed-off-by: Axel Lin <[email protected]>

Applied, thanks.

g.

> ---
> drivers/of/irq.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/of/irq.c b/drivers/of/irq.c
> index a3c1c5a..5c645c7 100644
> --- a/drivers/of/irq.c
> +++ b/drivers/of/irq.c
> @@ -482,8 +482,9 @@ void __init of_irq_init(const struct of_device_id *matches)
> }
>
> /* Get the next pending parent that might have children */
> - desc = list_first_entry(&intc_parent_list, typeof(*desc), list);
> - if (list_empty(&intc_parent_list) || !desc) {
> + desc = list_first_entry_or_null(&intc_parent_list,
> + typeof(*desc), list);
> + if (!desc) {
> pr_err("of_irq_init: children remain, but no parents\n");
> break;
> }
> --
> 1.8.1.2
>
>
>