Date: Fri, 23 Sep 2016 17:07:34 +0200
From: Greg KH <gregkh@linuxfoundation.org>
To: Aditya.Shankar@microchip.com
Cc: Ganesh.Krishna@microchip.com, nicolas.ferre@atmel.com,
        linux-wireless@vger.kernel.org, luisbg@osg.samsung.com
Subject: Re: staging: wilc1000: kernel Oops while opening the device
Message-ID: <20160923150734.GB13933@kroah.com> (sfid-20160923_170733_841196_03E49063)
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On Fri, Sep 23, 2016 at 01:17:08PM +0000, Aditya.Shankar@microchip.com wrote:
> On Thursday 22 September 2016 06:04 PM, Ganesh Krishna - I00112 wrote:
> >> -----Original Message-----
> >> From: Greg Kroah-Hartman [mailto:gregkh@linuxfoundation.org] 
> >> Sent: Monday, September 19, 2016 7:12 PM
> >> To: Nicolas Ferre
> >> Cc: linux-wireless@vger.kernel.org; Aditya Shankar - I16078; Ganesh Krishna - I00112; luisbg@osg.samsung.com
> >> Subject: Re: staging: wilc1000: kernel Oops while opening the device
> >>
> >> On Mon, Sep 19, 2016 at 02:06:02PM +0200, Nicolas Ferre wrote:
> >>> Hi all,
> >>>
> >>> While using the wilc1000 driver with latest 4.8-rc7, I have 
> >>> difficulties to open the device and actually use it as I have this 
> >>> kernel Oops right after the loading of the firmware (wilc1003_firmware.bin).
> >>>
> >>> If I revert back the driver to its 
> >>> b9811891a9f60ca9c314dcab3244c65930c4cf37 state, it works okay. I did 
> >>> this because I tend to think that it might be related to the latest move on this driver to "completion" or "work queues".
> >>> It seems to be a regression from 4.7.
> >>
> >> Ick, not good at all.
> >>
> >> Any chance you can run 'git bisect' to see if you can find the offending patch?
> >>
> >> I thought the maintainers were testing this driver over time :(
> > 
> >> thanks,
> >>
> >> greg k-h
> > 
> > Ick indeed. Maintainers are on it full time. Thank you very much for the flag. While I am only reporting activity, hope to have results soon.
> > Regards,
> > ganesh k 
> > 
> Hi All,
> 
> bisecting changes on the wilc1000 host driver, I find that this problem seems to occur after the below change. 
> As of now, I only know the where and not the why. So I will continue to figure out why this happens.
> 
> commit 2518ac59eb27ed003c5a97e8f9588adafdfe4a8a
> Author: Binoy Jayan <binoy.jayan@linaro.org>
> Date:   Thu Jun 23 11:11:51 2016 +0530
> 
>     staging: wilc1000: Replace kthread with workqueue for host interface
>     
>     Deconstruct the kthread / message_queue logic, replacing it with
>     create_singlethread_workqueue() / queue_work() setup, by adding a
>     'struct work_struct' to 'struct host_if_msg'. The current kthread
>     hostIFthread() is converted to a work queue helper with the name
>     'host_if_work'.

So if you revert this, it works?

If so, let us know and I will gladly revert it, as breaking things is
not ok.

thanks,

greg k-h