Re: [PATCH] x86/pci: add pci=skip_isa_align command lines.

["Yinghai Lu" <yhlu.kernel@gmail.com>]

On Thu, Mar 27, 2008 at 10:59 AM, Gary Hade <garyhade@us.ibm.com> wrote:
>
> On Thu, Mar 27, 2008 at 09:45:57AM +0100, Ingo Molnar wrote:
>  >
>  > * Yinghai Lu <yhlu.kernel.send@gmail.com> wrote:
>  >
>  > > [PATCH] x86/pci: add pci=skip_isa_align command lines.
>  > >
>  > > so we don't align the io port start address for pci cards.
>  > >
>  > > also move out dmi check out acpi.c, because it has nothing to do with
>  > > acpi. it could spare some calling when we have several peer root
>  > > buses.
>  >
>  > i like this feature, and i've applied your patch to x86.git for testing,
>  > but i'd like to hear what the ACPI and PCI guys think about this.
>  >
>  > Also, we should try as hard as possible to make it a blacklist instead
>  > of a whitelist? It would be cool to support more PCI cards/devices on
>  > all new(-ish) systems by default and if we didnt have to maintain the
>  > DMI whitelist for eternity. (a whitelist will always be incomplete and
>  > will lag behind reality)
>
>  Ingo, This is a great idea.  I was the guy that added the whitelist
>  and ISA alignment avoidance code but have also been concerned about
>  the headache of keeping whitelist current in mainline and Distro
>  releases as new systems are introduced.  When I made the change I
>  assumed (appearently incorrectly) that there were way too many
>  existing systems requiring the alignment to even consider the
>  blacklist approach.  Do you have any suggestions on how to identify
>  systems to include in the blacklist? ...or would we just boldly make
>  non-alignment the default, provide an empty blacklist, and let
>  breakage identify those systems that need to be blacklisted?

at least to use blacklist with x86_64

YH