Re: [PATCH] x86: add /proc/cpuinfo/physical id quirks

[Suresh Siddha <suresh.b.siddha@intel.com>]

On Thu, 2009-08-20 at 14:03 -0700, Andi Kleen wrote:
> > I am leaning towards sysfs, and prefer:
> > 
> >  	/sys/devices/system/cpu/$cpu/chassis_id
> > 
> > How does that sound?
> 
> I would prefer to simply use the existing physical id for this like
> in your original patch.  We already have a bewildering zoo of different
> CPU IDs, no need to increase the confusion even more.
> 
> Incidentially mcelog already knows how to use physical ID for this,
> would need to be changed for a new sysfs interface

Andi, Based on our past experiences, I am nervous if there are some
software/firmware interactions that can negatively affect the cpu
topology detection.

If we really think overloading the "physical id" helps with existing
software, then I am ok with changing the user visible part of the /proc/
or /sys files but not with the kernel's per cpu info's phys_proc_id,
which is used for topology detection etc.

thanks,
suresh