Re: kms in defconfig

Dave Airlie
2009-04-27T08:56:41Z

On Mon, Apr 27, 2009 at 6:39 PM, Ingo Molnar <mingo@elte.hu> wrote:
>
> * Dave Airlie <airlied@gmail.com> wrote:
>
>> Hi guys,
>>
>> I just noticed CONFIG_DRM_I915_KMS is enabled for x86-64.
>>
>> This should never be the case, as anyone who built defconfig
>> kernels before, will now get KMS enabled when really they need to
>> have done userspace upgrades.
>
> I've yet to see such a bugreport.
>
> But i dont have particularly strong feelings about defconfigs: less
> than 1% of all kernel developers use them - which transforms into
> less than 0.01% of all Linux users.
>
> KMS is off by default in 'make oldconfig', right? That's all that
> matters really.

My main worry is distro configs going forward, where they pull something
from defconfig, granted I've no idea if that'll happen, maybe distro kernel
maintainers are smarter than I give them credit for :-)

> defconfigs _do_ change and there was never a compatibility rule for
> defconfigs. Arch defconfig is more of a signal towards what the
> architecture maintainers consider sane and supportable (or
> desirable) defaults - and it is also what developers working on
> arch/x86 should consider as the main thrust of features.
>
> That's an extremely long period of migration. I also think it's
> unreasonable: we dont want to draw out the migration from
> DRI1+user-space-mode-setting to DRI2+KMS that long. KMS should have
> been implemented and made the default 4-5 years _ago_ i think.
>
> KMS is the sane design for graphics and i'd go as far as to consider
> user-space mode setting an outright _bug_. It look a long time to
> fix but now lets look forward and fix all the bugs in KMS, ASAP ...

Its mainly for things like Andrews Vaio, people will not expect a new kernel
to take out any current userspace, its a pain, but we assume distros + people
who compile their own kernels will know what userspace exists on their
machines and other will get the least surprise.

Dave.

>
>        Ingo
>