Comment 49 for bug 286285

Have exactly the same problem with a Lenovo Thinkpad T61:
After upgrade from Ubuntu 8.04 to 8.10, sometimes the following procs are consuming 1 of my cpu cores
no problems with 8.04.

system also will hang couple of times a day, see bug 292569, don't know if this has something to do with it.

Top output:
 5466 root 20 0 1940 544 448 R 56% 0.0 1:01.15 dd
 5468 klog 20 0 3768 2568 444 R 40% 0.1 0:58.18 klogd

ps-list
root 8765 1 35 12:04 ? 00:03:38 /bin/dd bs 1 if /proc/kmsg of /var/run/klogd/kmsg
klog 8767 1 33 12:04 ? 00:03:28 /sbin/klogd -P /var/run/klogd/kmsg

thanks to the fact these daemons are single-treathed, only one core is fully busy, so I can work.

part of the messages and syslog file:

Nov 2 11:53:50 roland-ppt kernel: [ 396.774834] bad: scheduling from the idle thread!
Nov 2 11:53:50 roland-ppt kernel: [ 396.774842] Pid: 0, comm: swapper Not taint 9 ick+0x0nxl0[3le+0x4b3/0x790
Nov 2 11:53:50 roland-ppt kernel: [ 396.776504] [<c0380ff5>] ? notifier_call_chain+0x35/0x70
Nov 2 11:53:50 roland-ppt kernel: [ 396.776509] [<c014cd6>7/7k] deactivate_tas[o>7= ] deactivate__[o>7/7] de3[[.ainted 2.6.27-7-generic #1
Nov 2 11:53:50 roland-ppt kernel: [ 396.779379] [<c037c406>] ? printk+0x1d/0x1f
Nov 2 11:53:50 roland-ppt kernel: [ 396.779384] [<c0122b8a>] dequeue_task_idle+0x2a/0x40
Nov 2 11:53:50 roland-ppt kernel: [ 396.779388] [<c012107f>] dequeue_task+0xcf/0x130
Nov 2 11:53:50 roland-ppt kernel: [ 396.779393] [<c012112a>] deactivate_task+0x1a/0x30
Nov 2 11:53:50 roland-ppt kernel: [ 396.779397] [<c037ca23>] schedule+0x4b3/0x790
Nov 2 11:53:50 roland-ppt kernel: [ 396.779400] [<c0380ff5>] ? notifier_call_chain+0x35/0x70
Nov 2 11:53:50 roland-ppt kernel: [ 396.779405] [<c0151b55>] ? clockevents_notify+0x35/0x80
Nov 2 11:53:50 roland-ppt kernel: [ 396.779423] [<f8875a43>] ? ticks_elapsed_in_us+0xb/0x4d [processor]
Nov 2 11:53:50 roland-ppt kernel: [ 396.779441] [<f88762d7>] ? acpi_state_timer_broadcast+0x36/0x39 [processor]
Nov 2 11:53:50 roland-ppt kernel: [ 396.779449] [<c0153d82>] ? tick_nohz_stop_idle+0x12/0x70
Nov 2 11:53:50 roland-ppt kernel: [ 396.779454] [<c0153e15>] ? tick_nohz_restart_sched_tick+0x35/0x180
Nov 2 11:53:50 roland-ppt kernel: [ 396.779458] [<c01028cd>] cpu_idle+0xbd/0x140
Nov 2 11:53:50 roland-ppt kernel: [ 396.779462] [<c037a661>] start_secondary+0x9d/0xcc

Find some identical problems which should be solved with Backports, following are installed on my PC:
linux-backports-modules-2.6.24-21-generic
linux-backports-modules-2.6.27-7-generic
linux-backports-modules-intrepid
linux-backports-modules-intrepid-generic

The same problems stay, with and withouth these backports

also removing the iwlagn module didn't give results, The lenovo T61 has the possibility to hardware-switch-off bluetooth and wireless, this also didn't give results.

regards Roland
Fenestras morituri erant, liber origo causidicus te salutant.