[natty] disappearing mouse cursor [MGA G550]

[Dave Gilbert]

This bug appeared somewhere between lucid (which was OK) and natty (which has this bug) - maverick wasn't tried long enough to notice.

The mouse cursor disappears on a bunch of applications when you wouldn't expect it; and flickers a lot - examples of where it happens include on the system menu child menus when tooltips appear, clicking on any of the menu bar entries in LibreOffice Writer, and the main window in Fldigi.

I tried nr_cpus=1 to see if it was an smpism, but it hasn't helped. I'm going to try swcursor.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: xserver-xorg-video-mga 1:1.4.13.dfsg-3build1
ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic i686
Architecture: i386
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
Date: Sat Jun 25 18:58:27 2011
DistUpgraded: Log time: 2011-06-20 16:12:16.102139
DistroCodename: natty
DistroVariant: ubuntu
GraphicsCard:
 Matrox Graphics, Inc. MGA G550 AGP [102b:2527] (rev 01) (prog-if 00 [VGA controller])
   Subsystem: Matrox Graphics, Inc. Millennium G550 Dual Head DDR 32Mb [102b:0f84]
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100429)
Lsusb:
 Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: Tyan Guinness
ProcEnviron:
 LANGUAGE=en_GB:en
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.38-8-generic root=UUID=95ba6ec1-173f-4096-8e78-f98b9e60a8b0 ro quiet splash vt.handoff=7 nr_cpus=1
Renderer: Unknown
SourcePackage: xserver-xorg-video-mga
UpgradeStatus: Upgraded to natty on 2011-06-20 (5 days ago)
dmi.bios.date: 12/12/2002
dmi.bios.vendor: Phoenix Technologies Ltd.
dmi.bios.version: PGNA02-8
dmi.board.name: Guinness
dmi.board.vendor: Tyan
dmi.board.version: EVT1
dmi.chassis.type: 2
dmi.chassis.vendor: Tyan
dmi.modalias: dmi:bvnPhoenixTechnologiesLtd.:bvrPGNA02-8:bd12/12/2002:svnTyan:pnGuinness:pvrEVT1:rvnTyan:rnGuinness:rvrEVT1:cvnTyan:ct2:cvr:
dmi.product.name: Guinness
dmi.product.version: EVT1
dmi.sys.vendor: Tyan
version.compiz: compiz 1:0.9.4+bzr20110606-0ubuntu1~natty1
version.libdrm2: libdrm2 2.4.23-1ubuntu6
version.libgl1-mesa-dri: libgl1-mesa-dri 7.10.2-0ubuntu2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 7.10.2-0ubuntu2
version.xserver-xorg: xserver-xorg 1:7.6+4ubuntu3
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.0-0ubuntu4
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.14.0-4ubuntu7.1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110107+b795ca6e-0ubuntu7

[Dave Gilbert (ubuntu-treblig)]

Hmm - I tried disabling HW cursor and it still happens - which makes me whether it's actually hardware specific; but I've not seen it on anything else.

The xorg.conf I put in to stop it was:
Section "Device"
  Identifier "Configured Video Device"
  Driver "mga"
  Option "SWCursor" "True"
  Option "HWCursor" "off"
EndSection

and /var/log/Xorg.0.log now includes:

[ 19.707] (**) MGA(0): Option "SWcursor" "True"
[ 19.707] (**) MGA(0): Option "HWcursor" "off"
[ 19.707] (==) MGA(0): Using AGP 1x mode
[ 19.708] (**) MGA(0): Using SW cursor

Odd.

Dave