lkml.org 
[lkml]   [2013]   [Nov]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
SubjectRE: [PATCH] [extcon]:remove freed groups caused the panic or warning in unregister flow
Date
Dear Choi

-----Original Message-----
From: Chanwoo Choi [mailto:cw00.choi@samsung.com]
Sent: Monday, November 04, 2013 9:43 AM
To: Wang, Xiaoming
Cc: myungjoo.ham@samsung.com; linux-kernel@vger.kernel.org; Liu, Chuansheng; Zhang, Dongxing
Subject: Re: [PATCH] [extcon]:remove freed groups caused the panic or warning in unregister flow

Hi Wang,

> drivers/extcon/extcon-class.c | 3 ++-
> 1 files changed, 2 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/extcon/extcon-class.c
> b/drivers/extcon/extcon-class.c index 148382f..48f4669 100644
> --- a/drivers/extcon/extcon-class.c
> +++ b/drivers/extcon/extcon-class.c
> @@ -794,6 +794,8 @@ void extcon_dev_unregister(struct extcon_dev *edev)
> return;
> }
>
> + device_unregister(edev->dev);
> +
> if (edev->mutually_exclusive && edev->max_supported) {
> for (index = 0; edev->mutually_exclusive[index];
> index++)
> @@ -814,7 +816,6 @@ void extcon_dev_unregister(struct extcon_dev *edev)
> if (switch_class)
> class_compat_remove_link(switch_class, edev->dev, NULL); #endif
> - device_unregister(edev->dev);
> put_device(edev->dev);
> }
> EXPORT_SYMBOL_GPL(extcon_dev_unregister);
>

I think we could only apply following patch instead of moving the position of device_unregister().

diff --git a/drivers/extcon/extcon-class.c b/drivers/extcon/extcon-class.c index 148382f..ff27b19 100644
--- a/drivers/extcon/extcon-class.c
+++ b/drivers/extcon/extcon-class.c
@@ -805,10 +805,8 @@ void extcon_dev_unregister(struct extcon_dev *edev)
for (index = 0; index < edev->max_supported; index++)
kfree(edev->cables[index].attr_g.name);

- if (edev->max_supported) {
- kfree(edev->extcon_dev_type.groups);
+ if (edev->max_supported)
kfree(edev->cables);
- }

#if defined(CONFIG_ANDROID)
if (switch_class)
Thanks,
Chanwoo Choi

I don't agree with you.
Why do not you want moving the position of device_unregister()?
It will cause the memory leak if has not kfree edev->extcon_dev_type.groups as your patch do firstly. And if you think kfree edev->extcon_dev_type.groups is meaningless well then kfree edev->extcon_dev_type.groups in function exton_dev_register (line 756)also should be removed I think. What do you think?

Thanks
Xiaoming.
\
 
 \ /
  Last update: 2013-11-04 03:41    [W:0.050 / U:0.340 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site