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From:   Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Date:   Fri, 3 Apr 2020 23:41:45 +0530
To:     Alan Stern <stern@rowland.harvard.edu>
Cc:     Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>,
        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
Message-ID: <20200403181145.GA7574@madhuparna-HP-Notebook>
References: <20200402232228.22395-1-madhuparnabhowmik10@gmail.com>
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On Fri, Apr 03, 2020 at 10:39:33AM -0400, Alan Stern wrote:
> 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.
>
Thank you for letting me know, I will send the patch again with this
change.

Regards,
Madhuparna

> Alan Stern
>