linux-kernel - Re: [PATCH 2/4] gpio: davinci: Handle the return value of davinci_gpio_irq

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 21 Jul 2017 09:23:01 +0530
From:   Keerthy <j-keerthy@...com>
To:     Grygorii Strashko <grygorii.strashko@...com>,
        Johan Hovold <johan@...nel.org>
CC:     <linus.walleij@...aro.org>, <ssantosh@...nel.org>,
        <devicetree@...r.kernel.org>, <nsekhar@...com>,
        <linux-kernel@...r.kernel.org>, <linux-gpio@...r.kernel.org>,
        <robh+dt@...nel.org>, <linux-arm-kernel@...ts.infradead.org>,
        <fcooper@...com>
Subject: Re: [PATCH 2/4] gpio: davinci: Handle the return value of
 davinci_gpio_irq_setup function



On Friday 21 July 2017 03:04 AM, Grygorii Strashko wrote:
> 
> 
> On 07/20/2017 05:05 AM, Johan Hovold wrote:
>> On Thu, Jul 20, 2017 at 03:32:27PM +0530, Keerthy wrote:
>>> On Thursday 20 July 2017 03:20 PM, Johan Hovold wrote:
>>>> On Thu, Jul 20, 2017 at 02:40:37PM +0530, Keerthy wrote:
>>>>> On Thursday 20 July 2017 12:14 PM, Keerthy wrote:
>>>>>> On Wednesday 19 July 2017 04:40 PM, Johan Hovold wrote:
>>
>>>>>>> There's a separate but related bug here too as the clk_prepare_enable()
>>>>>>> in davinci_gpio_irq_setup() is never balanced on driver unbind.
>>>>>>
>>>>>> Yes Johan. I will send that as a separate patch.
>>>>>
>>>>> This is already fixed in the latest kernel:
>>>>>
>>>>> commit 6dc0048cff988858254fcc26becfc1e9753efa79
>>>>> Author: Arvind Yadav <arvind.yadav.cs@...il.com>
>>>>> Date:   Tue May 23 14:48:57 2017 +0530
>>>>
>>>> That change only handles errors in davinci_gpio_irq_setup() (i.e. during
>>>> probe) and not the imbalance at driver unbind that I was referring to.
>>>
>>> Okay got it. One more clk_unprepare_disable() call needs to be there in
>>> probe err path.
>>
>> No, you need to balance it on driver unbind, that is, in a new remove()
>> callback.
>>
> 
> Sry, but manual driver unbind for this driver is really smth unexpected ;(
> So, I'm not sure if it need to be implemented and even yes - it should not be
> a part of this patch. Probably, smth like "convert driver to be a module".
> 

The GPIO_DAVINCI config is bool. Thanks for checking on that Grygorii.

> By the way, I've tried to unbind gpio-omap, result - failure (expected),
> as unbind does not take into account module refcnt state.

Okay.

> 
>