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

Luis Henriques
2014-12-19T13:51:27Z

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?

Cheers,
--
Luís

> cheers
>
> --
> balbi