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From: Dan Carpenter <dan.carpenter@oracle.com>
To: navin patidar <navinp@cdac.in>
Cc: gregkh@linuxfoundation.org, mfm@muteddisk.com,
	devel@driverdev.osuosl.org, linux-usb@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] staging: usbip: stub_dev: Fixed oops during removal of usbip_host
Date: Tue, 18 Sep 2012 12:36:19 +0300	[thread overview]
Message-ID: <20120918093619.GO13767@mwanda> (raw)
In-Reply-To: <CAPV97yda9d6yVbTfmET0Rj+xrRDniKzucfKCy=8gUbCDFYR5jg@mail.gmail.com>

On Tue, Sep 18, 2012 at 03:02:15PM +0530, navin patidar wrote:
> On Tue, Sep 18, 2012 at 1:10 PM, Dan Carpenter <dan.carpenter@oracle.com> wrote:
> > On Tue, Sep 18, 2012 at 09:30:06AM +0530, navin patidar wrote:
> >> stub_device_reset should set kernel thread pointers to NULL.
> >> so that at the time of usbip_host removal stub_shoutdown_connection
> >> doesn't try to kill kernel threads which are already killed.
> >>
> >
> > If you have the Oops output, that's always nice to put in the commit
> > message.
> 
> i'll surely keep this in mind  before submitting further patches.
> 
> > Why don't you set the pointers to NULL in stub_shutdown_connection()
> > since that's where you actually kill the threads.  Setting them to
> > NULL in stub_device_reset() will (sometimes) solve the problem but
> > it gives you a new problem of a resource leak.
> 
>  stub_device_reset() always gets executed after
> stub_shutdown_connection() , never before.
> 

No it isn't.  Read event_handler() more carefully.  They can be
executed independently.

In other words, stub_shutdown_connection() can be called without
calling stub_device_reset() and stub_device_reset() can be called
without stub_shutdown_connection().  If either of those happen then
it causes a problem with the patch you have just sent.

regards,
dan carpenter


  reply	other threads:[~2012-09-18  9:36 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-09-18  4:00 [PATCH] staging: usbip: stub_dev: Fixed oops during removal of usbip_host navin patidar
2012-09-18  7:40 ` Dan Carpenter
2012-09-18  9:32   ` navin patidar
2012-09-18  9:36     ` Dan Carpenter [this message]
2012-09-18 11:44       ` navin patidar
2012-09-18 13:15         ` Dan Carpenter
  -- strict thread matches above, loose matches on Subject: below --
2012-09-14 13:21 navin patidar
2012-09-14 14:16 ` Dan Carpenter
2012-09-14 14:28   ` Sebastian Andrzej Siewior
2012-09-14 14:41     ` Dan Carpenter
2012-09-14  9:53 navin patidar
2012-09-14 11:42 ` Sergei Shtylyov
2012-09-14 12:04   ` Sebastian Andrzej Siewior
2012-09-14 14:29     ` navin patidar
     [not found]   ` <CAPV97yfV27x8hB2WUCVmGWEU7i21Y5K5trig2fzQBx+VB_Yk2g@mail.gmail.com>
2012-09-14 14:16     ` Sergei Shtylyov
2012-09-17 12:19 ` Greg KH

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