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Date: Wed, 24 Aug 2011 22:25:46 +0530
Message-ID: <CAD2nsn1oD9mVOs7dUZNRrnkt=jnefDnaOMro8JFrUfK=7n1+Mw@mail.gmail.com> (sfid-20110824_185550_908531_738BF0FF)
Subject: Re: [RFC/RFT] ath9k_htc: Fix memory leak
From: Mohammed Shafi <shafi.wireless@gmail.com>
To: Larry Finger <Larry.Finger@lwfinger.net>
Cc: "John W. Linville" <linville@tuxdriver.com>,
	lrodriguez@atheros.com, vasanth@atheros.com,
	senthilkumar@atheros.com, ath9k-devel@venema.h4ckr.net,
	linux-wireless@vger.kernel.org, rmanohar@qca.qualcomm.com
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On Wed, Aug 24, 2011 at 10:19 PM, Larry Finger
<Larry.Finger@lwfinger.net> wrote:
> On 08/24/2011 10:53 AM, Mohammed Shafi wrote:
>>
>> On Wed, Aug 24, 2011 at 1:15 AM, John W. Linville
>> <linville@tuxdriver.com> ?wrote:
>>>
>>> On Mon, Aug 15, 2011 at 05:56:33PM +0530, Mohammed Shafi wrote:
>>>>
>>>> On Sun, Aug 14, 2011 at 7:04 AM, Larry Finger<Larry.Finger@lwfinger.net>
>>>> ?wrote:
>>>>>
>>>>> Kmemleak shows the following kind of memory leak for ath9k_htc:
>>>>>
>>>>> unreferenced object 0xffff88004542f200 (size 512):
>>>>> ?comm "khubd", pid 977, jiffies 4317632516 (age 16855.868s)
>>>>> ?hex dump (first 32 bytes):
>>>>> ? ?00 00 00 0a 00 00 00 00 00 02 01 05 00 00 02 01 ?................
>>>>> ? ?00 00 00 00 00 00 81 38 02 00 00 00 33 33 30 30 ?.......8....3300
>>>>> ?backtrace:
>>>>> ? ?[<ffffffff81122d77>] create_object+0x127/0x2b0
>>>>> ? ?[<ffffffff813580b1>] kmemleak_alloc+0x21/0x50
>>>>> ? ?[<ffffffff8111f383>] __kmalloc_node_track_caller+0x153/0x220
>>>>> ? ?[<ffffffff812b703e>] __alloc_skb+0x7e/0x170
>>>>> ? ?[<ffffffffa0833331>] htc_connect_service+0x111/0x200 [ath9k_htc]
>>>>> ? ?[<ffffffffa083bb90>] ath9k_init_htc_services+0x240/0x2b0 [ath9k_htc]
>>>>> ? ?[<ffffffffa083c1ca>] ath9k_htc_probe_device+0xea/0xa50 [ath9k_htc]
>>>>> ? ?[<ffffffffa08338dc>] ath9k_htc_hw_init+0xc/0x30 [ath9k_htc]
>>>>> ? ?[<ffffffffa08356ba>] ath9k_hif_usb_probe+0x1ca/0x420 [ath9k_htc]
>>>>> ? ?[<ffffffffa00a2279>] usb_probe_interface+0xb9/0x160 [usbcore]
>>>>> ? ?[<ffffffff81279379>] driver_probe_device+0x89/0x1a0
>>>>> ? ?[<ffffffff8127958b>] __device_attach+0x4b/0x60
>>>>> ? ?[<ffffffff81278024>] bus_for_each_drv+0x64/0x90
>>>>> ? ?[<ffffffff81279231>] device_attach+0xa1/0xb0
>>>>> ? ?[<ffffffff81278a25>] bus_probe_device+0x25/0x40
>>>>> ? ?[<ffffffff81276d2a>] device_add+0x55a/0x630
>>>>>
>>>>> The device is a TP-Link TL-WN722N. The output from lsusb is "ID
>>>>> 0cf3:9271
>>>>> Atheros Communications, Inc. AR9271 802.11n".
>>>>>
>>>>> Signed-off-by: Larry Finger<Larry.Finger@lwfinger.net>
>>>>> Cc: Stable<stable@kernel.org>
>>>>> ---
>>>>>
>>>>> This patch certainly fixes a leak. I'm testing to see if there are
>>>>> others.
>>>>
>>>> Hi Larry,
>>>>
>>>> thanks for finding this.
>>>> I remember seeing this memleaks sometime back and thought this patch
>>>> might help(i think same as yours with some more corner cases)
>>>> https://patchwork.kernel.org/patch/1016752/
>>>> but I found there were still some memory leaks, I was unsure where I
>>>> am missing. if you are sure that this addresses the issue, we can send
>>>> a patch.
>>>
>>> Ping? ?Is this the patch we want? ?Or something else?
>>
>> Hi John,
>>
>> the complete patch is posted
>> http://www.spinics.net/lists/linux-wireless/msg75134.html
>> Vasanth said that at some scenario's with the above patch it may cause
>> some panics.
>> based on the maintainers concerns/doubts lets drop this patch. myself
>> and Larry still noticed few more memory leaks. I think we better drop
>> this patch and fix it completely/tested. as I am with some other
>> critical tasks we will soon address this.
>>
>> Larry if you have any thoughts, please share.
>
> Dropping the current patches seems right with me. I hope to get time to work
> on this, but I also have some other things to do. Perhaps, we can get a
> patch with the subset of leaks in the error path that do not have any
> complications. Those would be easy, and then we can get the others later.

yes sure, once I get some time to test and understand this completely. thanks!

>
> Larry
>



-- 
shafi