Re: 5.15 regression: CONFIG_SYSFB_SIMPLEFB breaks console scrolling

[Thorsten Leemhuis <regressions@leemhuis.info>]

On 25.11.21 13:00, Thorsten Leemhuis wrote:
> On 21.11.21 12:47, Thorsten Leemhuis wrote:
>> Hi, this is your Linux kernel regression tracker speaking.
> /me again

and again :-D

>> On 16.11.21 05:52, Harald Dunkel wrote:
>>>
>>> if I enable CONFIG_SYSFB_SIMPLEFB in 5.15.2 and use grub's default
>>> configuration
>>> (Debian sid amd64), then a few lines at the bottom of /dev/tty1 including
>>> login prompt are off-screen. Scrolling is broken. I can login, though.
>>>
>>> Enabling GRUB_TERMINAL=console in grub doesn't make a difference. Using
>>> the same kernel except for CONFIG_SYSFB_SIMPLEFB the problem is gone.
>>>
>>> Graphics card is a GeForce GTX 1650. I tried with both CONFIG_DRM_NOUVEAU
>>> and proprietary graphics drivers disabled.
>>>
>>> Attached you can find the config file. Please mail if I can help to track
>>> this problem down.
>>
>> Thx for the report. I'm not totally sure if this is a regression, as
>> that's a new config option. But it might be one considered a successor
>> to an older one, hence it might count as regression. Adding two
>> developers and a mailing list to the CC, hopefully someone can clarify.
> 
> Javier, I'd be interested in your option on this.
> 
> Harald, did you have CONFIG_X86_SYSFB enabled in earlier kernel versions
> (and did console scrolling work then)? The answer would help me to
> decide if this a regression, as those ideally should be fixed as quickly
> as possible.

Harald, a reply would have been very helpful; I wonder if Javier is
waiting for the answer, too. If I get none in the next few days I guess
I'll drop this from the list of tracked regressions.

Ciao, Thorsten

#regzbot ignore-activity

>> TWIMC: To be sure this issue doesn't fall through the cracks unnoticed,
>> I'm adding it to regzbot, my Linux kernel regression tracking bot:
>>
>> #regzbot ^introduced 8633ef82f101c040427b57d4df7b706261420b94
>> #regzbot title CONFIG_SYSFB_SIMPLEFB breaks console scrolling
>> #regzbot ignore-activity
>>
>> Ciao, Thorsten, your Linux kernel regression tracker.
>>
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> 
> #regzbot title drm: CONFIG_SYSFB_SIMPLEFB breaks console scrolling
> 
> 
> 
>