[PATCH 1/8] Remove NACA fixed address constraint

[will schmidt]

David Boutcher wrote:
> Jeff Scheel <scheel at vnet.ibm.com> wrote on 08/09/2005 01:42:42 AM:
> 
>>On Mon, 2005-08-01 at 05:53, David Gibson wrote:
>>
>>>Comments in head.S suggest that the iSeries naca has a fixed address,
>>>because tools expect to find it there.  The only tool which appears to
>>>access the naca is addRamDisk, but both the in-kernel version and the
>>>version used in RHEL and SuSE in fact locate the NACA the same way as
>>>the hypervisor does, by following the pointer in the hvReleaseData
>>>structure.
>>>
>>>Since the requirement for a fixed address seems to be obsolete, this
>>>patch removes the naca from head.S and replaces it with a normal C
>>>initializer.
>>
>>There are IBM internal debug tools built into the iSeries which depend
>>on this address.  Removing it will break them.
>>
>>You should really get input from Mike Ranweiler as to the impact of this
>>change.  Dave Boutcher might also have insight.
>>-Jeff
> 
>  
> I was asked before this patch was sent..  No one that I am aware of
> has used these tools in a couple of years.
>  

A few of us folks down the hall from you have been using these tools a 
fair amount recently.   Not clear to me how significant the breakage 
is,.. but being an internal tool, that discussion belongs elsewhere.

Christoph Hellwig wrote:
 > Bad luch.  opensource the tools and they can be fixed.  Reliance on
 > binry only internal to some company tools must not hold kernel
 > development back.

Yes, you are right.  I cant argue against this point.

-Will