[PATCH 1/1] apple-gmux: Assign apple_gmux_data before registering

[Darren Hart]

On Mon, Nov 16, 2015 at 09:38:40PM +0100, Lukas Wunner wrote:
> From: Matthew Garrett <matthew.garrett at nebula.com>
> 
> Registering the handler after both GPUs will trigger a DDC switch for
> connector reprobing. This will oops if apple_gmux_data hasn't already
> been assigned. Reorder the code to do that.
> 
> [Lukas: More generally, this commit fixes a race condition that
> is triggered by invoking a handler callback between the call to
> vga_switcheroo_register_handler() and the assignment of
> apple_gmux_data.]
> 
> Tested-by: Pierre Moreau <pierre.morrow at free.fr>
>     [MBP  5,3 2009  nvidia MCP79 + G96        pre-retina  15"]
> Tested-by: Paul Hordiienko <pvt.gord at gmail.com>
>     [MBP  6,2 2010  intel ILK + nvidia GT216  pre-retina  15"]
> Tested-by: Lukas Wunner <lukas at wunner.de>
>     [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
> Tested-by: William Brown <william at blackhats.net.au>
>     [MBP  8,2 2011  intel SNB + amd turks     pre-retina  15"]
> Tested-by: Bruno Bierbaumer <bruno at bierbaumer.net>
>     [MBP 11,3 2013  intel HSW + nvidia GK107  retina      15"]
> 
> Signed-off-by: Matthew Garrett <matthew.garrett at nebula.com>
> Reviewed-by: Lukas Wunner <lukas at wunner.de>
> Signed-off-by: Lukas Wunner <lukas at wunner.de>

My apologies for the delay. Thank you for the testing data and submitting.

I have queued this to testing. Pending success on 0-day, it will land in
linux-next shortly (tomorrow most likely) where I hope it will receive
additional testing.

-- 
Darren Hart
Intel Open Source Technology Center