[PATCH V2] mfd: abx500-core: Fix compiler warning larger stack frame

Lee Jones
2014-05-21T09:17:51Z

> Change from V1 -> V2: Fix a potential null pointer dereference as reported by kbuild test robot <fengguang.wu@intel.com>.
>
> Inorder to report the kzalloc failure, I have just used a pr_debug statement. If it looks ugly, should I change the function's return value to int and give out an -ENOMEM ?

Yes, please do that - and obviously add the checks to the calling code.

> From 6615c7a995a6bb4dcf4c1e9ac59bca823ec821a5 Mon Sep 17 00:00:00 2001
> From: Aurabindo J <mail@aurabindo.in>
> Date: Wed, 21 May 2014 11:18:10 +0530
> Subject: [PATCH] mfd: abx500-core: Fix compiler warning larger stack frame
>
> On systems with CONFIG_FRAME_WARN=1024, compiler warns the allocation of
> an object of struct device on stack. Make the allocation dynamically to
> fix the warning.
>
> Signed-off-by: Aurabindo J <mail@aurabindo.in>
> ---
> drivers/mfd/abx500-core.c | 19 ++++++++++++-------
> 1 file changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/mfd/abx500-core.c b/drivers/mfd/abx500-core.c
> index f3a15aa..5e5098d 100644
> --- a/drivers/mfd/abx500-core.c
> +++ b/drivers/mfd/abx500-core.c
> @@ -154,16 +154,21 @@ EXPORT_SYMBOL(abx500_startup_irq_enabled);
> void abx500_dump_all_banks(void)
> {
> struct abx500_ops *ops;
> - struct device dummy_child = {NULL};
> + struct device *dummy_child;
> struct abx500_device_entry *dev_entry;
>
> - list_for_each_entry(dev_entry, &abx500_list, list) {
> - dummy_child.parent = dev_entry->dev;
> - ops = &dev_entry->ops;
> + dummy_child = kzalloc(sizeof(struct device), GFP_KERNEL);
> + if (dummy_child != NULL) {
> + list_for_each_entry(dev_entry, &abx500_list, list) {
> + dummy_child->parent = dev_entry->dev;
> + ops = &dev_entry->ops;
>
> - if ((ops != NULL) && (ops->dump_all_banks != NULL))
> - ops->dump_all_banks(&dummy_child);
> - }
> + if ((ops != NULL) && (ops->dump_all_banks != NULL))
> + ops->dump_all_banks(dummy_child);
> + }
> + kfree(dummy_child);
> + } else
> + pr_debug("kzalloc failure in abx500_dump_all_banks\n");
> }
> EXPORT_SYMBOL(abx500_dump_all_banks);