Nouveau - Jun 2019 - [PATCH 18/22] mm: mark DEVICE_PUBLIC as broken

On Thu 13-06-19 11:43:21, Christoph Hellwig wrote:
> The code hasn't been used since it was added to the tree, and
doesn't
> appear to actually be usable.  Mark it as BROKEN until either a user
> comes along or we finally give up on it.
I would go even further and simply remove all the DEVICE_PUBLIC code.
> Signed-off-by: Christoph Hellwig <hch at lst.de>
Anyway
Acked-by: Michal Hocko <mhocko at suse.com>
> ---
>  mm/Kconfig | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 0d2ba7e1f43e..406fa45e9ecc 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -721,6 +721,7 @@ config DEVICE_PRIVATE
>  config DEVICE_PUBLIC
>  	bool "Addressable device memory (like GPU memory)"
>  	depends on ARCH_HAS_HMM
> +	depends on BROKEN
>  	select HMM
>  	select DEV_PAGEMAP_OPS
>  
> -- 
> 2.20.1
-- 
Michal Hocko
SUSE Labs

On Thu, Jun 20, 2019 at 09:26:48PM +0200, Michal Hocko
wrote:
> On Thu 13-06-19 11:43:21, Christoph Hellwig wrote:
> > The code hasn't been used since it was added to the tree, and
doesn't
> > appear to actually be usable.  Mark it as BROKEN until either a user
> > comes along or we finally give up on it.
> 
> I would go even further and simply remove all the DEVICE_PUBLIC code.
I looked into that as I now got the feedback twice.  It would
create a conflict with another tree cleaning things up around the
is_device_private defintion, but otherwise I'd be glad to just remove
it.

Jason, as this goes through your tree, do you mind the additional
conflict?

On Tue, Jun 25, 2019 at 09:29:15AM +0200, Christoph Hellwig
wrote:
> On Thu, Jun 20, 2019 at 09:26:48PM +0200, Michal Hocko wrote:
> > On Thu 13-06-19 11:43:21, Christoph Hellwig wrote:
> > > The code hasn't been used since it was added to the tree, and
doesn't
> > > appear to actually be usable.  Mark it as BROKEN until either a
user
> > > comes along or we finally give up on it.
> > 
> > I would go even further and simply remove all the DEVICE_PUBLIC code.
> 
> I looked into that as I now got the feedback twice.  It would
> create a conflict with another tree cleaning things up around the
> is_device_private defintion, but otherwise I'd be glad to just remove
> it.
> 
> Jason, as this goes through your tree, do you mind the additional
> conflict?
Which tree and what does the resolution look like?

Also, I don't want to be making the decision if we should keep/remove
DEVICE_PUBLIC, so let's get an Ack from Andrew/etc?

My main reluctance is that I know there is HW out there that can do
coherent, and I want to believe they are coming with patches, just
too slowly. But I'd also rather those people defend themselves :P

Thanks,
Jason