Re: Clocksource tsc is always unstable with 2.6.25-* kernels and CONFIG_NO_HZ=y on my box

[Gabriel C <nix.or.die@googlemail.com>]

Thomas Gleixner wrote:
> On Sun, 24 Feb 2008, Robert Hancock wrote:
>> Gabriel C wrote:
>>> Hi,
>>>
>>> I noticed tsc is always marked unstable on my box with 2.6.25* , 2.6.24 is
>>> fine.
>>>
>>> ..
>>>
>>> [    0.825760] ACPI: PCI Interrupt 0000:03:0e.0[A] -> GSI 22 (level, low) ->
>>> IRQ 22
>>> [    0.805755] Switched to high resolution mode on CPU 1
>>> [    0.794244] Switched to high resolution mode on CPU 2
>>> [    0.766968] Switched to high resolution mode on CPU 3
>>> [    1.083944] Switched to high resolution mode on CPU 0
>>> [   15.388792] Clocksource tsc unstable (delta = 9373391604 ns)
> 
> Doh, this looks like the acpi_pm timer is not working at all.
> 
>>> [   15.714648] Time: acpi_pm clocksource has been installed.
>>> ..
>>>
>>> Booting nohz=off fixes that.
>>>
>>> Another strange thing is when I try to boot that kernel with
>>> clocksource=acpi_pm it just hangs.
> 
> Which confirms the above.
>  
>>> config is attached.
>>>
>>> Please let me know if you need more infos / want me to try patches or
>>> anything else.
>> Please post your full dmesg output.
> 
> Yes please.

dmesg's from 2.6.25-rc3 witch nohz={on,off} , lspci , dmidecode and the used config for this kernel can be found there :

http://frugalware.org/~crazy/dmesg/lara/

> 
> Thanks,
> 	tglx
> 


Regards,

Gabriel