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Date:   Fri, 3 Apr 2020 10:39:33 -0400 (EDT)
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
cc:     gregkh@linuxfoundation.org, <hariprasad.kelam@gmail.com>,
        <colin.king@canonical.com>, <linux-usb@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <ldv-project@linuxtesting.org>,
        <andrianov@ispras.ru>
Subject: Re: [PATCH] usb: host: u132-hcd: Remove u132_static_list
In-Reply-To: <20200402232228.22395-1-madhuparnabhowmik10@gmail.com>
Message-ID: <Pine.LNX.4.44L0.2004031038200.7035-100000@netrider.rowland.org>
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On Fri, 3 Apr 2020 madhuparnabhowmik10@gmail.com wrote:

> From: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
> 
> u132_static_list is a global list protected by u132_module_lock.
> It is read in the u132_hcd_exit() function without holding the lock
> thus may lead to data race.
> However, it turns out that this list isn't used for anything useful
> and thus it is okay to get rid of it.
> Thus, remove the u132_static_list from u132-hcd module.
> 
> Found by Linux Driver Verification project (linuxtesting.org).
> 
> Suggested-by: Alan Stern <stern@rowland.harvard.edu>
> Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
> ---
>  drivers/usb/host/u132-hcd.c | 8 --------
>  1 file changed, 8 deletions(-)
> 
> diff --git a/drivers/usb/host/u132-hcd.c b/drivers/usb/host/u132-hcd.c
> index e9209e3e6248..52f70cf063ea 100644
> --- a/drivers/usb/host/u132-hcd.c
> +++ b/drivers/usb/host/u132-hcd.c
> @@ -81,7 +81,6 @@ static DECLARE_WAIT_QUEUE_HEAD(u132_hcd_wait);
>  static struct mutex u132_module_lock;
>  static int u132_exiting;
>  static int u132_instances;
> -static struct list_head u132_static_list;
>  /*
>  * end of the global variables protected by u132_module_lock
>  */

You forgot to remove the u132_list member from struct u132.

Alan Stern