After some user switches using either the switch user appet or "switch from..." or on the login screen, my computer hangs.
Note that this does not happen every time I switch users, only after about every 3rd switch. The only resolution I found for the freeze is a cold restart.
My hardware is a Lenovo W500 laptop, with 2 graphic adapters. I disabled the ATI adapter in the BIOS, ubuntu thus only sees the Intel adapter. lspci reports it as:
00:02.0 VGA compatible controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 07)
Here is the adapter info from Xorg.log:
(--) PCI:*(0:0:2:0) 8086:2a42:17aa:2114 Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller rev 7, Mem @ 0xf4400000/4194304, 0xd0000000/268435456, I/O @ 0x00001800/8
(--) PCI: (0:0:2:1) 8086:2a43:17aa:2114 Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller rev 7, Mem @ 0xf4200000/1048576
I found the follwing report in my Xorg.log, making me strongly believe the graphics adapter is the problem here.
(II) intel(0): Modeline "1920x1200"x0.0 125.66 1920 1950 2030 2060 1200 1202 1206 1220 -hsync -vsync (61.0 kHz)
[mi] EQ overflowing. The server is probably stuck in an infinite loop.
Backtrace:
0: /usr/bin/X (xorg_backtrace+0x3b) [0x80e937b]
1: /usr/bin/X (mieqEnqueue+0x1ab) [0x80e8b6b]
2: /usr/bin/X (xf86PostKeyEventP+0x7c) [0x80c276c]
3: /usr/bin/X (xf86PostKeyboardEvent+0x4b) [0x80c283b]
4: /usr/lib/xorg/modules/input/evdev_drv.so (0xb6e79000+0x4bfd) [0xb6e7dbfd]
5: /usr/bin/X (0x8048000+0x6d5bf) [0x80b55bf]
6: /usr/bin/X (0x8048000+0x122794) [0x816a794]
7: (vdso) (__kernel_sigreturn+0x0) [0xb787e400]
8: /usr/lib/xorg/modules/libfb.so (fbOddTile+0x118) [0xb739fa48]
9: /usr/lib/xorg/modules/libfb.so (fbTile+0x8c) [0xb739fb0c]
10: /usr/lib/xorg/modules/libfb.so (fbFill+0x36f) [0xb739766f]
11: /usr/lib/xorg/modules/libfb.so (fbPolyFillRect+0x1b4) [0xb7397964]
12: /usr/lib/xorg/modules/drivers/intel_drv.so (0xb73bc000+0x63392) [0xb741f392]
13: /usr/lib/xorg/modules/drivers/intel_drv.so (0xb73bc000+0x5ce0d) [0xb7418e0d]
14: /usr/bin/X (0x8048000+0xd9195) [0x8121195]
15: /usr/bin/X (miPaintWindow+0x1c2) [0x809ef82]
16: /usr/bin/X (miWindowExposures+0xc7) [0x809f317]
17: /usr/bin/X (0x8048000+0x1386d8) [0x81806d8]
18: /usr/bin/X (miHandleValidateExposures+0x78) [0x81b26c8]
19: /usr/bin/X (0x8048000+0x7839f) [0x80c039f]
20: /usr/bin/X (xf86EnableDisableFBAccess+0x74) [0x80c0464]
21: /usr/lib/xorg/modules/drivers/intel_drv.so (0xb73bc000+0x5b412) [0xb7417412]
22: /usr/bin/X (0x8048000+0x144454) [0x818c454]
23: /usr/bin/X (xf86Wakeup+0x23f) [0x80b5a6f]
24: /usr/bin/X (WakeupHandler+0x52) [0x80779f2]
25: /usr/bin/X (WaitForSomething+0x1a2) [0x80a3f92]
26: /usr/bin/X (0x8048000+0x2a1b0) [0x80721b0]
27: /usr/bin/X (0x8048000+0x1ed7a) [0x8066d7a]
28: /lib/tls/i686/cmov/libc.so.6 (__libc_start_main+0xe6) [0xb75b6bd6]
29: /usr/bin/X (0x8048000+0x1e961) [0x8066961]
Please advise how to solve this problem
---
Architecture: i386
DistroRelease: Ubuntu 10.04
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100429)
MachineType: LENOVO 4061AD4
Package: xorg 1:7.5+5ubuntu1
PackageArchitecture: i386
PccardctlIdent:
Socket 0:
no product info available
PccardctlStatus:
Socket 0:
no card
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.32-22-generic-pae root=UUID=f2b5ebf2-28ed-4116-86ff-3c4cfe5f79b0 ro quiet splash
ProcEnviron:
PATH=(custom, user)
LANG=en_US.UTF-8
SHELL=/bin/bash
LC_PAPER=en_GB.UTF-8
ProcVersionSignature: Ubuntu 2.6.32-22.36-generic-pae 2.6.32.11+drm33.2
Tags: lucid lucid
Uname: Linux 2.6.32-22-generic-pae i686
UserGroups: adm admin cdrom dialout dip fax floppy fuse lpadmin plugdev sambashare tape video
dmi.bios.date: 11/26/2009
dmi.bios.vendor: LENOVO
dmi.bios.version: 6FET82WW (3.12 )
dmi.board.name: 4061AD4
dmi.board.vendor: LENOVO
dmi.board.version: Not Available
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvr6FET82WW(3.12):bd11/26/2009:svnLENOVO:pn4061AD4:pvrThinkPadW500:rvnLENOVO:rn4061AD4:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 4061AD4
dmi.product.version: ThinkPad W500
dmi.sys.vendor: LENOVO
glxinfo: Error: [Errno 2] No such file or directory
system:
distro: Ubuntu
codename: lucid
architecture: i686
kernel: 2.6.32-22-generic-pae
might be related to: Bug #583345, Bug #567696
and to the blank screen problems (which I have also seen): Bug #546578