Re: [PATCH] x86/split_lock: Restore warn mode (and add a new one) to avoid userspace regression

From: Guilherme G. Piccoli
Date: Thu Sep 29 2022 - 11:30:42 EST


On 29/09/2022 12:17, Dave Hansen wrote:
> [...]
>> Hi Dave, thanks for your response. I really appreciated your reasoning,
>> and I think it's a good argument. In the end, adding misery would harm
>> the users that are unlikely to be able to fix (or at least, fix quickly)
>> the split lock situation, like games or legacy/proprietary code.
>>
>> I have a revert removing the misery ready and tested, let me know if I
>> should submit it.
>
> I'm a bit of a late arrival to the split lock party, so I'm a bit
> hesitant to merge any changes immediately.
>

OK, agree that we could indeed gather more opinions, like Thomas' and
other interested parties. But...


> How about we give it a few weeks and see if the current behavior impacts
> anyone else? Maybe the best route will be more clear then.

...I disagree in just letting it fly for weeks with all players of God
of War 2 running modern Intel chips unable to play in 5.19+ because of
this change.

Certainly we have more games/applications that are impacted, I just
don't think we should wait on having 3 userspace breakages reported, for
example, to take an action - why should gamers live with this for an
arbitrary amount of time, until others report more issues?

Cheers,


Guilherme