Hello,
I don't think this is a BIOS issue, but a kernel bug in the i386 tree. I believe this was recently discussed and hopefully fixed by Andi Kleen in the kernel mailing list:
http://lkml.org/lkml/2006/1/9/442
This is a critical bug especially for systems running AMD Dual-Core Processors on i386 kernel configuration w/ powernow-k8.
The reason for "powernow-k8 - out of sync" errors is because the cpufreq driver is not aware [or has the wrong idea] about which CPUs are tied together, because cpu_core_id and phy_proc_id data is wrong.
Now this is fairly harmless as Mark mentioned, but only on single socket Dual Core systems.
On a multi-socket multi-core system, it will result in something like: (2 dual-core Opterons)
cpu0:
drwxr-xr-x 2 root root 0 Nov 3 09:51 cpufreq
cpu1:
drwxr-xr-x 2 root root 0 Nov 3 09:51 cpufreq
cpu2:
lrwxrwxrwx 1 root root 0 Nov 3 09:51 cpufreq -> ../../../../devices/system/cpu/cpu1/cpufreq
cpu3:
lrwxrwxrwx 1 root root 0 Nov 3 09:51 cpufreq -> ../../../../devices/system/cpu/cpu1/cpufreq
In this configuration, the second processors will never be able to be managed by a governor.
I was wondering if anyone has already tested Andi's patch, if it successfully solves this problem, and if the patch has made it into the git yet.
Thanks,
-Jacob Shin
AMD, Inc.
On [email protected] wrote:
>>> You'll get that message on an Athlon X2 if you're using an
>>> old version of the driver that doesn't fully support
>>> dual core or if your part is being reported to Linux as 2 single core parts.
>>>
>>> Neither of those should be happening with the 2.6.15.1 kernel.
>>
>> OK, seems we've really found a bug then.
>
> Yes, but it's a BIOS bug.
>
>>> Could you send me the results of `dmesg | grep powern` immediately
>>> after boot?
>>
>> Sure:
>> # dmesg|grep powern
>> powernow-k8: Found 2 AMD Athlon 64 / Opteron processors (version 1.50.4)
>> powernow-k8: 0 : fid 0xc (2000 MHz), vid 0x8 (1350 mV)
>> powernow-k8: 1 : fid 0xa (1800 MHz), vid 0xa (1300 mV)
>> powernow-k8: 2 : fid 0x2 (1000 MHz), vid 0x12 (1100 mV)
>> powernow-k8: 0 : fid 0xc (2000 MHz), vid 0x8 (1350 mV)
>> powernow-k8: 1 : fid 0xa (1800 MHz), vid 0xa (1300 mV)
>> powernow-k8: 2 : fid 0x2 (1000 MHz), vid 0x12 (1100 mV)
>
> You're using a driver that supports dual-core, but the BIOS
> is reporting the two cores as two separate processors.
> They've probably got the APICIDs misconfigured.
>
> I've reported it to FSC and I advise you to do the same.
>
>> powernow-k8: error - out of sync, fix 0xc 0x2, vid 0x8 0x12
>> powernow-k8: error - out of sync, fix 0x2 0xa, vid 0x12 0xa
>> powernow-k8: error - out of sync, fix 0xa 0xc, vid 0xa 0x8
>> powernow-k8: error - out of sync, fix 0xc 0x2, vid 0x8 0x12
>> powernow-k8: error - out of sync, fix 0x2 0xc, vid 0x12 0x8
>> powernow-k8: error - out of sync, fix 0xc 0x2, vid 0x8 0x12
>
> These messages are mostly harmless, by the way, but some
> people have seen system instability. I would enable
> pmtimer support as your clock source, but that's advisable
> when running a single dual-core anyway.
>
> -Mark Langsdorf
> AMD, Inc.
>
>
> _______________________________________________
> Cpufreq mailing list
> [email protected]
> http://lists.linux.org.uk/mailman/listinfo/cpufreq
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