Incomplete stable drm/ast backport - screen freeze on boot

[Jocelyn Falempe]

On 13/11/2023 17:37, Sasha Levin wrote:
> On Mon, Nov 13, 2023 at 10:49:01AM +0100, Thomas Zimmermann wrote:
>> (cc: gregkh)
>>
>> Hi Jocelyn
>>
>> Am 13.11.23 um 10:36 schrieb Jocelyn Falempe:
>>> On 13/11/2023 09:34, Keno Fischer wrote:
>>>> Greetings,
>>>>
>>>> When connected to a remote machine via the BMC KVM functionality,
>>>> I am experiencing screen freezes on boot when using 6.5 stable,
>>>> but not master.
>>>>
>>>> The BMC on the machine in question is an ASpeed AST2600.
>>>> A quick bisect shows the problematic commit to be 2fb9667
>>>> ("drm/ast: report connection status on Display Port.").
>>>> This is commit f81bb0ac upstream.
>>>>
>>>> I believe the problem is that the previous commit in the series
>>>> e329cb5 ("drm/ast: Add BMC virtual connector")
>>>> was not backported to the stable branch.
>>>> As a consequence, it appears that the more accurate DP state detection
>>>> is causing the kernel to believe that no display is connected,
>>>> even when the BMC's virtual display is in fact in use.
>>>> A cherry-pick of e329cb5 onto the stable branch resolves the issue.
>>>
>>> Yes, you're right this two patches must be backported together.
>>>
>>> I'm sorry I didn't pay enough attention, that only one of the two was 
>>> picked up for the stable branch.
>>>
>>> Is it possible to backport e329cb5 to the stable branch, or should I 
>>> push it to drm-misc-fixes ?
>>
>> I think stable, which is in cc, will pick up commit e329cb5 
>> semi-automatically now. Otherwise, maybe ping gregkh in a few days 
>> about it.
> 
> I thikn it would be more appropriate to revert 2fb9667, as e329cb5
> doesn't look like -stable material. I'll go ahead and do that.
> 
Ok, that's the best thing to do, as Thomas also found that userspace can 
be confused by the new BMC virtual connector, so it's safer to revert.

Thanks,

-- 

Jocelyn