Re: Blank screen on boot of Linux 6.5 and later on Lenovo ThinkPad L570

From: Linux regression tracking (Thorsten Leemhuis)
Date: Fri Oct 20 2023 - 05:35:53 EST


On 09.10.23 10:54, Huacai Chen wrote:
> On Mon, Oct 9, 2023 at 4:45 PM Bagas Sanjaya <bagasdotme@xxxxxxxxx> wrote:
>> On Mon, Oct 09, 2023 at 09:27:02AM +0800, Huacai Chen wrote:
>>> On Tue, Sep 26, 2023 at 10:31 PM Huacai Chen <chenhuacai@xxxxxxxxxx> wrote:
>>>> On Tue, Sep 26, 2023 at 7:15 PM Linux regression tracking (Thorsten
>>>> Leemhuis) <regressions@xxxxxxxxxxxxx> wrote:
>>>>> On 13.09.23 14:02, Jaak Ristioja wrote:
>>>>>>
>>>>>> Upgrading to Linux 6.5 on a Lenovo ThinkPad L570 (Integrated Intel HD
>>>>>> Graphics 620 (rev 02), Intel(R) Core(TM) i7-7500U) results in a blank
>>>>>> screen after boot until the display manager starts... if it does start
>>>>>> at all. Using the nomodeset kernel parameter seems to be a workaround.
>>>>>>
>>>>>> I've bisected this to commit 60aebc9559492cea6a9625f514a8041717e3a2e4
>>>>>> ("drivers/firmware: Move sysfb_init() from device_initcall to
>>>>>> subsys_initcall_sync").
>>>>>
>>>>> Hmmm, no reaction since it was posted a while ago, unless I'm missing
>>>>> something.
>>>>>
>>>>> Huacai Chen, did you maybe miss this report? The problem is apparently
>>>>> caused by a commit of yours (that Javier applied), you hence should look
>>>>> into this.
>>>> I'm sorry but it looks very strange, could you please share your config file?
>>> As confirmed by Jaak, disabling DRM_SIMPLEDRM makes things work fine
>>> again. So I guess the reason:
>>
>> Did Jaak reply privately? It should have been disclosed in public
>> ML here instead.
> Yes, he replied privately, and disabling DRM_SIMPLEDRM was suggested by me.

Well, this to me still looks a lot (please correct me if I'm wrong) like
regression that should be fixed, as DRM_SIMPLEDRM was enabled beforehand
if I understood things correctly. Or is there a proper fix for this
already in the works and I just missed this? Or is there some good
reason why this won't/can't be fixed?

Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
--
Everything you wanna know about Linux kernel regression tracking:
https://linux-regtracking.leemhuis.info/about/#tldr
If I did something stupid, please tell me, as explained on that page.

#regzbot poke

>>> When SIMPLEDRM takes over the framebuffer, the screen is blank (don't
>>> know why). And before 60aebc9559492cea6a9625f ("drivers/firmware: Move
>>> sysfb_init() from device_initcall to subsys_initcall_sync") there is
>>> no platform device created for SIMPLEDRM at early stage, so it seems
>>> also "no problem".
>>
>> I don't understand above. You mean that after that commit the platform
>> device is also none, right?
> No. The SIMPLEDRM driver needs a platform device to work, and that
> commit makes the platform device created earlier. So, before that
> commit, SIMPLEDRM doesn't work, but the screen isn't blank; after that
> commit, SIMPLEDRM works, but the screen is blank.
>
> Huacai
>>
>> Confused...
>>
>> --
>> An old man doll... just what I always wanted! - Clara
>
>