[Intel-gfx] i915 / 3.15 intermittently boots into blank screeen

[Jan Niggemann]

Forgot to Cc the list, sorry.

Am 18.07.2014 18:25, schrieb Daniel Vetter:
> On Fri, Jul 18, 2014 at 4:49 PM, Jan Niggemann <jn at hz6.de> wrote:
>>
>> Am 18.07.2014 15:27, schrieb Daniel Vetter:
>>>
>>> On Thu, Jul 17, 2014 at 10:31:30PM +0200, Jan Niggemann wrote:
>>>>
>>>> I'm experiencing an issue with 3.15.5 on my Lenovo T400:
>>>> Since 3.15 (or 3.14, can't say for sure), the boot starts 
>>>> normally, but
>>>> the
>>>> first mode change doesn't occur, resulting in a black screen with
>>>> backlight
>>>> on. The system is entirely unresponsive and I can only press the 
>>>> power
>>>> button until to switch it off.
>>>
>>> I think the only way to move forward here is to double-check that 
>>> 3.14
>>>
>>> works and 3.15 is broken by recompiling with the same .config
>>> (occasionally config changes cause regressions). And then do a full 
>>> git
>>> bisect to find the offending commit.
>>
>> thank you for the feedback.
>> I still have all my custom built kernels, I will test 3.14.0 through 
>> 3.14.8
>> to make sure those were OK and report back.
>
> You only need to test 3.14.0, since the backported fixes only contain
> a very small subset of all patches for 3.15. So it's more efficient 
> to
> then switch to git bisect between 3.14 and 3.15 directly (after 
> you've
> confirmed that 3.15.0 is indeed busted).
I now booted my custom 3.14.1 some 30 times, the issue didn't show 
once. It seems that it is indeed the 3.15 line that's borked.
I uploaded my custom 3.14.1 and 3.15.1 config files here: 
http://files.hz6.de/kernel-configs-jn.tgz

May this be related to this mail 
http://www.mail-archive.com/intel-gfx@lists.freedesktop.org/msg42432.html
"fix freeze with blank screen booting highmem" by Hugh Dickins?

Kind regards
jan