# KMS or not?

## Gear.0

When I first set up my kernel (2.6.34-r1) I used kernel-seeds.org as a guide. In that guide there is this line:

 *Quote:*   

> i915 driver
> 
> [*] Enable modesetting on intel by default
> 
> is not recommended or supported by me. I do not support KMS in any way. I use VESA VGA frame buffer and the above drm setup with [ ] Enable modesetting on intel by default. This disables KMS, compiles the Intel drm into the kernel, and makes X more stable, even when switching between X and CLI sessions with <Fn> keys.

 

I use the i915 driver, so naturally, being new to compiling a kernel and not knowing what modesetting is, I took the advice of this guide. I have no problems with this.

The reason I am writing this is because I had (have) an issue where I cannot get my laptop monitor to display its native resolution of (1400x1050) (laptop model is HP compaq nc6320)

Someone then mentioned that I should use KMS and that in fact I would be required to use it in later kernel versions or video won't work right at all (something like that).

Anyways... I've been putting off updating my kernel because of that, but I figure it's time.. So when I configure the latest kernel what do you guys think.. should I follow the guide (which still says that btw: maybe it just hasn't been updated?) Or should I enable KMS?

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## asturm

That advice cannot be universally applied. What exact hardware do you have? KMS works perfectly on my GMA 4500MHD, running on 2.6.36 and xorg-server-1.9.0. It took some time to reach that state though.

Anyway, it is also wrong that video wouldn't work without KMS in later kernels. You need to keep your xf86-video-intel version down, because non-KMS code was dropped with 2.10 or so (don't nail me down on the exact number).

So, what keeps you from simply trying out whether (non-)KMS does work or not in latest kernel?

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## Gear.0

 *genstorm wrote:*   

> So, what keeps you from simply trying out whether (non-)KMS does work or not in latest kernel?

 

Well nothing really. I am actually starting to reconfigure the kernel and was planning on trying KMS. I just was wondering if there will be any subtle problems I might have that may not be obvious at first.

Also, I ask because if KMS will eventually be the "standard" then I may as well get it working now.

[EDIT]

Sorry.. My video card is just an integrated intel one.Last edited by Gear.0 on Fri Nov 12, 2010 5:12 pm; edited 1 time in total

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## asturm

It kind of is the standard already, Intel doesn't care for non-KMS drivers since months. And for all the issues I had until 2.6.35 and pre-xorg-server-1.9.0, I never thought about going back to a dumb and inflexible uvesafb setup (switching between different external and built-in monitors all the time).

@Gear.0: Mine too.  :Wink:  It still has a model name.

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## chithanh

http://www.gentoo.org/doc/en/xorg-config.xml also tells you (how) to enable KMS.

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