Re: [RESEND PATCH] usb: gadget: at91_udc: move prepare clk into process context

Ronald Wahl
2014-12-19T14:08:57Z

On 19.12.2014 14:51, Luis Henriques wrote:
> Hi Felipe,
>
> On Thu, Nov 20, 2014 at 01:50:49PM -0600, Felipe Balbi wrote:
>> On Wed, Nov 19, 2014 at 04:37:27PM +0100, Nicolas Ferre wrote:
>>> From: Ronald Wahl <ronald.wahl@raritan.com>
>>>
>>> Commit 7628083227b6bc4a7e33d7c381d7a4e558424b6b (usb: gadget: at91_udc:
>>> prepare clk before calling enable) added clock preparation in interrupt
>>> context. This is not allowed as it might sleep. Also setting the clock
>>> rate is unsafe to call from there for the same reason. Move clock
>>> preparation and setting clock rate into process context (at91udc_probe).
>>>
>>> Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com>
>>> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
>>> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
>>> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
>>> Cc: Felipe Balbi <balbi@ti.com>
>>> Cc: <stable@vger.kernel.org> # v3.17+
>>> ---
>>> Hi Felipe,
>>>
>>> I forgot to answer you on this patch. So I resend it now with the proper
>>> "stable" tag. You can also queue it during this -rc phase if you feel it is
>>> still possible.
>>
>> I think it's late for v3.18, so it'll go on v3.19 and get backported to
>> 3.17 and 3.18. Sorry :-s
>>
>
> Although this commit (b2ba27a5c56f "usb: gadget: at91_udc: move
> prepare clk into process context") is tagged for stable v3.17+, it
> seems like it could be applied to earlier kernels.
>
> 3.16, 3.13 and 3.12 seem to be affected by the same issue (and they
> all include commit 7628083227b6 "usb: gadget: at91_udc: prepare clk
> before calling enable"). Is there any reason for not applying it in
> these trees?

Not to forget 3.14 (LTS) which was the branch where I primarily found
the issue...

- ron

--
Ronald Wahl - ronald.wahl@raritan.com - Phone +49 375271349-0 Fax -99
Raritan Deutschland GmbH, Kornmarkt 7, 08056 Zwickau, Germany
USt-IdNr. DE813094160, Steuer-Nr. 227/117/01749
Amtsgericht Chemnitz HRB 23605
Geschäftsführung: Stuart Hopper, Ralf Ploenes