linux-kernel - Re: [PATCH] HID: force setting drvdata to NULL when removing the driver

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] [day] [month] [year] [list]

Date:   Tue, 2 Apr 2019 16:02:53 +0200
From:   Hans de Goede <hdegoede@...hat.com>
To:     Benjamin Tissoires <benjamin.tissoires@...hat.com>
Cc:     Dmitry Torokhov <dmitry.torokhov@...il.com>,
        Jiri Kosina <jikos@...nel.org>,
        Bruno Prémont <bonbons@...ux-vserver.org>,
        Jonathan Cameron <jic23@...nel.org>,
        Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
        Jason Gerecke <killertofu@...il.com>,
        Ping Cheng <pinglinux@...il.com>,
        "linux-input@...r.kernel.org" <linux-input@...r.kernel.org>,
        lkml <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] HID: force setting drvdata to NULL when removing the
 driver

Hi,

On 02-04-19 16:00, Benjamin Tissoires wrote:
> On Tue, Apr 2, 2019 at 3:52 PM Hans de Goede <hdegoede@...hat.com> wrote:
>>
>> Hi,
>>
>> On 02-04-19 15:44, Benjamin Tissoires wrote:
>>> Hi Dmitry,
>>>
>>> On Fri, Mar 29, 2019 at 11:26 PM Dmitry Torokhov
>>> <dmitry.torokhov@...il.com> wrote:
>>>>
>>>> Hi Benjamin,
>>>>
>>>> On Thu, Mar 28, 2019 at 8:52 AM Benjamin Tissoires
>>>> <benjamin.tissoires@...hat.com> wrote:
>>>>>
>>>>> Or when the probe failed.
>>>>>
>>>>> This is a common pattern in the HID drivers to reset the drvdata. Some
>>>>> do it properly, some do it only in case of failure.
>>>>> Anyway, it's never a good thing to have breadcrumbs, so force a clean
>>>>> state when removing or when probe is failing.
>>>>
>>>> Just a data point: driver core already clears drvdata, so as long as
>>>> dev_get/set_drvdata() is the same as hid_get/set_drvdata() no special
>>>> handling is needed in HID core.
>>>
>>> You are correct (as always ;-P). I'll drop the hid-core changes and
>>> send a v2 ASAP.
>>
>> I was just looking at the same thing. I should have known about this
>> since I wrote the patch to make the core clear drvdata. I should have
>> mentioned that, but I was assuming that the hid code was special somehow,
>> however now I see it just uses a regular device_add, so indeed the core
>> changes are not necessary.
>>
>> Given the large hid-logitech-*.c patch-set it might be easier for
>> Jiri if you split out the hid-logitech-*.c changes into a separate
>> patch, then he can keep that on his logitech branch (just a thought).
>>
> 
> I do not expect the logitech changes to now create some big conflict.
> But looking at the current for-5.2* branches, I should probably split
> the series per driver given that there is no more dependency on
> hid-core. This way, we can take the logitech changes in the
> for-5.2/logitech branch, and you can rebase your work on top of it.

Great, thank you.

Regards,

Hans