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Date:   Thu, 8 Dec 2022 17:51:18 +0100
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Subject: Re: [PATCH 0/8] can: usb: remove all usb_set_intfdata(intf, NULL) in
 drivers' disconnect()
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To:     Vincent MAILHOL <mailhol.vincent@wanadoo.fr>,
        Oliver Neukum <oneukum@suse.com>
Cc:     Marc Kleine-Budde <mkl@pengutronix.de>, linux-can@vger.kernel.org,
        Wolfgang Grandegger <wg@grandegger.com>,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Frank Jungclaus <frank.jungclaus@esd.eu>, socketcan@esd.eu,
        Yasushi SHOJI <yashi@spacecubics.com>,
        =?UTF-8?Q?Stefan_M=c3=a4tje?= <stefan.maetje@esd.eu>,
        Hangyu Hua <hbh25y@gmail.com>,
        Oliver Hartkopp <socketcan@hartkopp.net>,
        Peter Fink <pfink@christ-es.de>,
        Jeroen Hofstee <jhofstee@victronenergy.com>,
        =?UTF-8?Q?Christoph_M=c3=b6hring?= <cmoehring@christ-es.de>,
        John Whittington <git@jbrengineering.co.uk>,
        Vasanth Sadhasivan <vasanth.sadhasivan@samsara.com>,
        Jimmy Assarsson <extja@kvaser.com>,
        Anssi Hannula <anssi.hannula@bitwise.fi>,
        Pavel Skripkin <paskripkin@gmail.com>,
        Stephane Grosjean <s.grosjean@peak-system.com>,
        Wolfram Sang <wsa+renesas@sang-engineering.com>,
        "Gustavo A . R . Silva" <gustavoars@kernel.org>,
        Julia Lawall <Julia.Lawall@inria.fr>,
        Dongliang Mu <dzm91@hust.edu.cn>,
        Sebastian Haas <haas@ems-wuensche.com>,
        Maximilian Schneider <max@schneidersoft.net>,
        Daniel Berglund <db@kvaser.com>,
        Olivier Sobrie <olivier@sobrie.be>,
        =?UTF-8?B?UmVtaWdpdXN6IEtvxYLFgsSFdGFq?= 
        <remigiusz.kollataj@mobica.com>,
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        Martin Elshuber <martin.elshuber@theobroma-systems.com>,
        Bernd Krumboeck <b.krumboeck@gmail.com>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Alan Stern <stern@rowland.harvard.edu>,
        linux-usb@vger.kernel.org
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From:   Oliver Neukum <oneukum@suse.com>
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On 08.12.22 16:44, Vincent MAILHOL wrote:
> On Thu. 8 Dec. 2022 at 20:04, Oliver Neukum <oneukum@suse.com> wrote:
>> On 08.12.22 10:00, Vincent MAILHOL wrote:
>>> On Mon. 5 Dec. 2022 at 17:39, Oliver Neukum <oneukum@suse.com> wrote:
>>>> On 03.12.22 14:31, Vincent Mailhol wrote:
>>
>> Good Morning!
> 
> Good night! (different time zone :))

Good evening!

> 
> How do you check that disconnect() has proceeded *to a given point*
> using intf without being racy? You can check if it has already
> completed once but not check how far it has proceeded, right?

You'd use intfdata, which is a pointer stored in intf.

But other than that the simplest way would be to use a mutex.


	Regards
		Oliver