[PATCH] Revert "drm/xe/devcoredump: Add ASCII85 dump helper function"

[Souza, Jose]

On Fri, 2024-12-13 at 09:50 -0600, Lucas De Marchi wrote:
> On Fri, Dec 13, 2024 at 03:24:59PM +0000, Jose Souza wrote:
> > On Fri, 2024-12-13 at 07:10 -0800, José Roberto de Souza wrote:
> > > On Fri, 2024-12-13 at 08:38 -0600, Lucas De Marchi wrote:
> > > > On Fri, Dec 13, 2024 at 09:12:52AM -0500, Rodrigo Vivi wrote:
> > > > > We do not break userspace.
> > > 
> > > There is other patch that also breaks Mesa parser:
> > > 
> > > drm/xe/devcoredump: Improve section headings and add tile info
> > > 
> > > > > 
> > > > > This reverts commit ec1455ce7e35a31289d2dbc1070b980538698921.
> > > > 
> > > > But we have users calling this function.... the revert is not so simple.
> > > > I think we need to revert the functionality rather than reverting all
> > > > the patches, otherwise it will cause a lot of headaches.
> > > > 
> > > > I propose we go with:
> > > > 
> > > > a) drop the \n that broke mesa and merge that with cc stable.
> > > > 
> > > > b) move back the entry to the previous section that broke mesa and cc
> > > >     stable.
> > > > 
> > > >     José, would it be ok to merge a patch in mesa and port that
> > > >     to mesa stable that simply looks at 2 possible sections? Or even
> > > >     drop the section checks... ?
> > 
> > But if Xe KMD is reverting the patch that changed the hwctx section why would Mesa need to also parse the new(future to be reverted) section?
> 
> first is to undo the damage, with 0 changes in mesa. We do that first and
> *then* we agree on what's possible to do to accomodate the 2 parsers we
> have.
> 
> If we can get something in mesa to work that is backward compatible (i.e. the
> changed parser is able to parse both before and after the kernel change),
> then it could be considered to a mesa stable and the kernel side
> changed.

Okay, reasonable plan. But the ascii85 encoder with \n will not be brought back right?
With that I can write the Mesa patch to support both sections, then it is up to other Mesa team members agree with it.

> 
> Lucas De Marchi
> 
> > I could CC the Mesa stable but it would not be picked to all Mesa versions with the devcoredump parser.
> > 
> > 
> > > > 
> > > > c) settle on one of the possible solutions for \n that were presented in
> > > >     this discussion.  I think the sanest one is that a space in the end of a
> > > >     line printing ascii85 would signify a continuation marker.  But merging
> > > >     (a) means we have time to discuss and adjust if needed.
> > > > 
> > > > After the dust settles we may think of a better way to evolve the
> > > > devcoredump format so it doesn't cause breakages in future updates.
> > > > 
> > > > Lucas De Marchi
> > > 
> >