Re: PCIE ASPM support hangs my laptop pretty often

[Greg KH <greg@kroah.com>]

On Wed, Feb 06, 2008 at 01:46:22PM -0800, Kok, Auke wrote:
> 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.

It's already reverted.

thanks,

greg k-h