Created attachment 100279 [details] [review]
workaround

hopefully attached workaround gives clues to what's up ..

Reproduced on Sandy Bridge, not on Haswell.

Created attachment 100298 [details]
screenshot

here's a screenshot from SNB desktop

Created attachment 100355 [details]
workaround

A bit more debugging update, the failure comes when using opcode SHADER_OPCODE_TEX, fs_visitor has different functions for gen7 and gen5 for emitting these. gen7 sets some payload with instruction so it never calls the same constructor and is not affected.

Attached workaround fixes the problem by doing same exact thing for opcode SHADER_OPCODE_TEX that happened before the change. I will continue to investigate possible better fix.

Huh. Seems really weird that the texture's source is implicit. I wonder why we do that instead of just making the MRF source explicit.

I am also getting these garbled graphics on Ubuntu 14.04, Unity and the intel ironlake.

http://www.phoronix.com/forums/showthread.php?50038-Updated-and-Optimized-Ubuntu-Free-Graphics-Drivers/page116

(In reply to comment #6)
> I am also getting these garbled graphics on Ubuntu 14.04, Unity and the
> intel ironlake.
> 
> http://www.phoronix.com/forums/showthread.php?50038-Updated-and-Optimized-
> Ubuntu-Free-Graphics-Drivers/page116

do you have a mesa git hash (which exact mesa are you runinng) for checking if this is the same thing?

It is mesa 10.3.0-git from the latest update of the Oibaf ppa. I am sorry, I am not sure what a git-hash is. How do I check?

Open a console and type the following command:

dpkg -l | grep libgl1

You will see something like this:

ii  libgl1-mesa-dri:amd64                                       10.3~git1405280730.ecee4c~gd~t              amd64        free implementation of the OpenGL API -- DRI modules
ii  libgl1-mesa-dri:i386                                        10.3~git1405280730.ecee4c~gd~t              i386         free implementation of the OpenGL API -- DRI modules
ii  libgl1-mesa-glx:amd64                                       10.3~git1405280730.ecee4c~gd~t              amd64        free implementation of the OpenGL API -- GLX runtime
ii  libgl1-mesa-glx:i386                                        10.3~git1405280730.ecee4c~gd~t              i386         free implementation of the OpenGL API -- GLX runtime

Copy the 10.3~git1405280730.ecee4c~gd~t equivalent value in the output of your console. (In my output, the letters after the dot, i.e. ecee4c, are the begining of the git hash version. From those letters we can know the git version the oibaf drivers you are using)

Hi,

Here it is

10.3~git1406041930.3642ee~gd~t

(In reply to comment #10)
> Hi,
> 
> Here it is
> 
> 10.3~git1406041930.3642ee~gd~t

thanks, then this is likely the same issue (also bug #79624).

Created attachment 100441 [details] [review]
hopeful fix

This patch initializes src register structure, otherwise we feed uninitialized brw_src to gen_texture call.

Hi

Unfortunately, still not fixed after the latest update

10.3~git1406051930.221169~gd~t

*** Bug 79690 has been marked as a duplicate of this bug. ***

*** Bug 79624 has been marked as a duplicate of this bug. ***

Created attachment 100515 [details] [review]
alternative patch to tackle this issue

here's another possible fix

Comment on attachment 100441 [details] [review]
hopeful fix

Review of attachment 100441 [details] [review]:
-----------------------------------------------------------------

I'd modify the fs_inst constructor in the visitor code to have a reg_undef src0 argument, since that's functionally identical to this code before my change.

Hi,

Still no improvement with tbe latest update

10.3~git1406071930.40500e~gd~t

Not sure if this would be of any help. I have just rolled my system back to the state before the problematic updates that seem to have broken everything since a little more than a week ago 

My last working version was

10.3~git1405280730.ecee4c~gd~t

(In reply to comment #17)
> Comment on attachment 100441 [details] [review] [review]
> hopeful fix
> 
> Review of attachment 100441 [details] [review] [review]:
> -----------------------------------------------------------------
> 
> I'd modify the fs_inst constructor in the visitor code to have a reg_undef
> src0 argument, since that's functionally identical to this code before my
> change.

I sent a patch that fixes the Piglit errors for me. Note that gen4 is probably broken too. I don't have the HW to prove it but I think logic goes the same way (?)

Bug is still present in 10.3~git1406081930.eb58aa~gd~t

Intel® Core™ i3 CPU 530 @ 2.93GHz × 4
Intel® Ironlake Desktop

I've committed Tapani's patch. Thanks!

Upgraded to 10.3~git1406100730.7a4527~gd~t a few hours ago, the bug is fixed for me (Intel Ironlake)
Thanks a lot!