Intel HD 540 green lines in mipmaps

[Nicolas_G_2]

System Setup Information:
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System Used: Surface Pro 4
CPU SKU: i7-6650U
GPU SKU: Iris Graphics 540
Processor Line: U-series
System BIOS Version: 104.1085.768
CMOS settings: ?
Graphics Driver Version: 20.19.15.4404
GOP/VBIOS Version: ?
Operating System: Windows 10 Pro
OS Version: 10.0.10586
API: Direct3D 11
Occurs on non-Intel GPUs?: No

Steps to Reproduce:
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1. "Download ZIP"  from https://github.com/nlguillemot/silver-winner/tree/d1381b67d08dd05bd56954441319011dfeae77b6
2. Open vsproj/silver-winner.sln using Visual Studio 2015 update 2
3. Build and run solution by pressing Local Windows Debugger
4. Observe scene (hold right mouse button and move mouse/press WASD to move)

Expected Results:
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Scene looks like an ordinary textured scene

Actual Results:
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Green lines are on top of objects past a certain distance

Additional Information:
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I haven't looked deeply into this, but I suspect there's a skylake D3D11 bug with mipmaps.

I've recorded a video of this in my own application: https://twitter.com/nlguillemot/status/717681988325355520

But the same bug also affected The Witness: http://imgur.com/a/m4WLH

The bug no longer affects The Witness because I reported it to the developers, who patched it by disabling mipmaps for the particular SKU (Iris 540)

I wouldn't be surprised if this is somehow my fault, but the fact that it happens in these 2 applications and that it doesn't happen on NVIDIA makes me suspicious that either there's a driver bug or some unexpected default values. Also, this happens for the diffuse textures in my program which use the sRGB format, so maybe it's specifically sRGB mipmapping that causes problems.

[Michael_C_Intel2]

Hi Nicolas,

Thanks for getting me all the details, this helps a lot. I am working with the driver team to investigate the problem and will let you know what we find out.

-Michael 

[Nicolas_G_2]

I've noticed that the problem goes away if I do the GenerateMips on a DXGI_FORMAT_R8G8B8A8_UNORM format instead of the DXGI_FORMAT_R8G8B8A8_UNORM_SRGB format. Therefore, I suspect that generating mips on a SRGB SRV is where the problem is.

[Michael_C_Intel2]

We found the problem and created a fix for the graphics driver. The fix should be available in the next public driver release.