Comment 5 for bug 17599

I have the same problem with the same Laptop under breezy, IBM Thinkpad T40p:
ksoftirqd/0 takes up all the processing power, the processor goes up to 1,6 GHz.

I'm using Kernel 2.6.12-9-386.

It seems to be related to switching of Wifi, with the Atheros module still
loaded. It happens using the Fn+F5 Switch or doing
sudo echo -n 3 > /sys/class/net/ath0/device/power/state
in console.
It is enough to switch the Wifi card back on to let the precesor state go back down.

ras@Nero:~$ lspci
0000:00:00.0 Host bridge: Intel Corp. 82855PM Processor to I/O Controller (rev 0 3)
0000:00:01.0 PCI bridge: Intel Corp. 82855PM Processor to AGP Controller (rev 03 )
0000:00:1d.0 USB Controller: Intel Corp. 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) US
B UHCI Controller #1 (rev 01)
0000:00:1d.1 USB Controller: Intel Corp. 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) US
B UHCI Controller #2 (rev 01)
0000:00:1d.2 USB Controller: Intel Corp. 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) US
B UHCI Controller #3 (rev 01)
0000:00:1d.7 USB Controller: Intel Corp. 82801DB/DBM (ICH4/ICH4-M) USB 2.0 EHCI
Controller (rev 01)
0000:00:1e.0 PCI bridge: Intel Corp. 82801 PCI Bridge (rev 81)
0000:00:1f.0 ISA bridge: Intel Corp. 82801DBM LPC Interface Controller (rev 01)
0000:00:1f.1 IDE interface: Intel Corp. 82801DBM (ICH4) Ultra ATA Storage Contro
ller (rev 01)
0000:00:1f.3 SMBus: Intel Corp. 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) SMBus Contr
oller (rev 01)
0000:00:1f.5 Multimedia audio controller: Intel Corp. 82801DB/DBL/DBM (ICH4/ICH4
-L/ICH4-M) AC'97 Audio Controller (rev 01)
0000:00:1f.6 Modem: Intel Corp. 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) AC'97 Modem
 Controller (rev 01)
0000:01:00.0 VGA compatible controller: ATI Technologies Inc Radeon R250 Lf [Rad
eon Mobility 9000 M9] (rev 02)
0000:02:00.0 CardBus bridge: Texas Instruments PCI1520 PC card Cardbus Controlle
r (rev 01)
0000:02:00.1 CardBus bridge: Texas Instruments PCI1520 PC card Cardbus Controlle
r (rev 01)
0000:02:01.0 Ethernet controller: Intel Corp. 82540EP Gigabit Ethernet Controlle
r (Mobile) (rev 03)
0000:02:02.0 Ethernet controller: Atheros Communications, Inc. AR5211 802.11ab N
IC (rev 01)
ras@Nero:~$ lsmod
Module Size Used by
binfmt_misc 10888 1
rfcomm 34972 0
l2cap 22404 5 rfcomm
ipv6 217408 8
speedstep_centrino 7380 1
cpufreq_userspace 4444 1
cpufreq_stats 5124 0
freq_table 4484 2 speedstep_centrino,cpufreq_stats
cpufreq_powersave 1920 0
cpufreq_ondemand 5916 0
cpufreq_conservative 6820 0
pcmcia 24584 4
radeon 68352 1
drm 58004 2 radeon
video 16004 0
tc1100_wmi 6916 0
sony_acpi 5516 0
pcc_acpi 11392 0
ibm_acpi 17908 0
hotkey 9508 0
dev_acpi 11396 0
i2c_acpi_ec 5760 0
i2c_core 19728 1 i2c_acpi_ec
button 6672 0
battery 9604 0
container 4608 0
ac 4996 0
af_packet 20232 2
wlan_wep 5888 1
irtty_sir 7808 0
sir_dev 17324 1 irtty_sir
irda 159804 2 irtty_sir,sir_dev
crc_ccitt 2176 1 irda
floppy 52692 0
rtc 11832 0
pcspkr 3652 0
hci_usb 13192 0
bluetooth 43012 5 rfcomm,l2cap,hci_usb
ath_pci 69148 0
ath_rate_sample 14344 1 ath_pci
wlan 120988 4 wlan_wep,ath_pci,ath_rate_sample
ath_hal 148432 3 ath_pci,ath_rate_sample
yenta_socket 22540 2
rsrc_nonstatic 12032 1 yenta_socket
pcmcia_core 44932 3 pcmcia,yenta_socket,rsrc_nonstatic
snd_intel8x0 30144 1
snd_ac97_codec 72188 1 snd_intel8x0
snd_pcm_oss 46368 0
snd_mixer_oss 16128 1 snd_pcm_oss
snd_pcm 78344 3 snd_intel8x0,snd_ac97_codec,snd_pcm_oss
snd_timer 21764 1 snd_pcm
snd 48644 8 snd_intel8x0,snd_ac97_codec,snd_pcm_oss,snd_mixe
r_oss,snd_pcm,snd_timer
soundcore 9184 1 snd
snd_page_alloc 10120 2 snd_intel8x0,snd_pcm
tpm_atmel 5504 0
tpm_nsc 6528 0
tpm 9504 2 tpm_atmel,tpm_nsc
hw_random 5268 0
shpchp 80612 0
pci_hotplug 24628 1 shpchp
intel_agp 21276 1
agpgart 32328 2 drm,intel_agp
dm_mod 50364 1
joydev 9280 0
tsdev 7616 0
evdev 9088 1
psmouse 26116 0
mousedev 10912 1
parport_pc 31812 1
lp 11460 0
parport 32072 2 parport_pc,lp
md 40656 0
ext3 115976 2
jbd 48536 1 ext3
thermal 13192 0
processor 23100 2 speedstep_centrino,thermal
fan 4740 0
e1000 89780 0
ehci_hcd 29448 0
uhci_hcd 28048 0
usbcore 104188 4 hci_usb,ehci_hcd,uhci_hcd
ide_cd 36996 0
cdrom 33952 1 ide_cd
ide_disk 16128 4
ide_generic 1664 0
piix 9476 1
ide_core 125268 4 ide_cd,ide_disk,ide_generic,piix
unix 24624 882
vesafb 8088 0
capability 5000 0
commoncap 6784 1 capability
vga16fb 12232 1
vgastate 8320 1 vga16fb
softcursor 2432 2 vesafb,vga16fb
cfbimgblt 2944 2 vesafb,vga16fb
cfbfillrect 3840 2 vesafb,vga16fb
cfbcopyarea 4480 2 vesafb,vga16fb
fbcon 34176 72
tileblit 2560 1 fbcon
font 8448 1 fbcon
bitblit 5248 1 fbcon