Kernel Bug Tracker – Bug 42984
scrabled video with nouveau drivers on mac mini (320m)
Last modified: 2013-05-27 19:45:42 UTC
I had this problem with ubuntu 11.10 and every other distro. tried it in both bios emulation and efi. the efi is broken with or without KMS. I suspect this is because under efi the same driver is being used in KMS or UMS whereas in bios emulation, the nomodeset option in grub loads the vesa driver.
right now in using kernel 3.2.1 and it the same problem with every distro you can think of.
the video chip is 320m. I have tried it on a mbp with intel graphics and it works perfect under efi and bios.
fixed with kernel 3.3 with bios emulation. although I don't actually know if this was caused by the kernel itself.
Unfortunately back in 3.4-rc3. Using a Macbook Air 3,2 also with a Nvidia 320M chip.
i wish the enterprise distros like RHEL and debian had some shame and just used vesa for the trouble models until nouveau was fixed.
Still present in 3.4-rc5.
is bios emulation or efi?
(In reply to comment #5)
> is bios emulation or efi?
Doesn't matter. Neither works. Information is available in the Ubuntu bug report https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-nouveau/+bug/898784.
Is there a way to change the regression tag to Yes?
Still present in 3.4-rc6.
how can we confirm that this is a kernel bug? can the problem be with something in the userspace?
If I boot a 3.2 kernel the bug is there, with a 3.3 kernel it is gone, and with a 3.4 kernel it is back. All other software remains the same.
(In reply to comment #11)
eDP-1 connected 1440x900+1920+0 (normal left inverted right x axis y axis) 286mm x 179mm
dithering depth: auto
supported: auto 6 bpc 8 bpc
dithering mode: auto
supported: auto off static 2x2 dynamic 2x2
scaling mode: Full
supported: None Full Center Full aspect
color vibrance: 150 (0x00000096) range: (0,200)
vibrant hue: 90 (0x0000005a) range: (0,180)
Any variant of xrandr --output eDP-1 --set dithering i have tried fails with
X Error of failed request: BadName (named color or font does not exist)
Major opcode of failed request: 150 (RANDR)
Minor opcode of failed request: 11 (RRQueryOutputProperty)
Serial number of failed request: 29
Current serial number in output stream: 29
Since dithering is reported as both a mode and a depth I don't know how to set up the xrandr command. Google is not being very friendly on the matter.
However, this would still not answer why a 3.3 kernel works and 3.2 or 3.4 do not.
The bug is still present in kernel 3.4.0 final. Anybody on how to test the dithering?
it's not dithering. the whole image is garbled. it's not a line pattern.
This bug is fixed with commit a6a17859f1b and can be closed. It's backported to 3.2 stable and 3.4 with confirmation on 3.2.27