Re: PCIE ASPM support hangs my laptop pretty often

["Kok, Auke" <auke-jan.h.kok@intel.com>]

Rafael J. Wysocki wrote:
> On Wednesday, 6 of February 2008, Pavel Machek wrote:
>> On Tue 2008-02-05 16:22:55, Kok, Auke wrote:
>>> ?????? ??????????? wrote:
>>>>>>>> I've patched my kernel with the PCIe ASPM and after setting
>>>>>>>> echo powersave > /sys/module/pcie_aspm/parameters/policy
>>>>>>>>
>>>>>>>> I started to experience random hangs of my laptop.
>>>>>>>> Hardware info:
>>>>>>>> Thinkpad x60s 1704-5UG
>>>>>>> the x60's chipset doesn't support ASPM properly afaik... bad idea.
>>>>>> Well, the code shouldn't then cause a crash of the machine :)
>>>>> The user enabled it specifically (where it is disabled by default)
>>>>>
>>>>> ASPM has been crashing e1000(e), which is why I've recently merged a patch
>>>>> to disable L1 ASPM for the onboard 82573 nic on those platforms.
>>>>>
>>>>> this new infrastructure should work in the default configuration - enabling
>>>>> ASPM where this system leaves it disabled is expected to give problems
>>>>> unless you know what you are doing.
>>>> In my defense, the patch documentation didn't say it doesn't work with my 
>>>> hardware, nor that it hangs the chipset :) and the promised 1.3w surelly 
>>>> looked nice.
>>>>
>>>> So, are there any benefits of ASPM if I have it in the kernel but it's set to 
>>>> default? I got the impression that "default" means not much power savings?
>>> did the Kconfig not come with a big fat (EXPERIMENTAL) ?
>> (EXPERIMENTAL) is something different from (KNOWN BROKEN).
>>
>> If we know about broken setups, we should probably be blacklisting
>> them.
> 
> Well, the ASPM thing seems to break every single setup I've tested.  So,
> perhaps we should whitelist the working ones?

greg KH is reverting this patch alltogether in mainline, maybe the original writer
can accomodate some of the comments in the rewrite.

Auke