Re: [PATCH 20/22] mm: sort out the DEVICE_PRIVATE Kconfig mess

[Jason Gunthorpe]

On Thu, Jun 13, 2019 at 11:43:23AM +0200, Christoph Hellwig wrote:
> The ZONE_DEVICE support doesn't depend on anything HMM related, just on
> various bits of arch support as indicated by the architecture.  Also
> don't select the option from nouveau as it isn't present in many setups,
> and depend on it instead.
> 
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
>  drivers/gpu/drm/nouveau/Kconfig | 2 +-
>  mm/Kconfig                      | 5 ++---
>  2 files changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/nouveau/Kconfig b/drivers/gpu/drm/nouveau/Kconfig
> index dba2613f7180..6303d203ab1d 100644
> +++ b/drivers/gpu/drm/nouveau/Kconfig
> @@ -85,10 +85,10 @@ config DRM_NOUVEAU_BACKLIGHT
>  config DRM_NOUVEAU_SVM
>  	bool "(EXPERIMENTAL) Enable SVM (Shared Virtual Memory) support"
>  	depends on ARCH_HAS_HMM
> +	depends on DEVICE_PRIVATE
>  	depends on DRM_NOUVEAU
>  	depends on STAGING
>  	select HMM_MIRROR
> -	select DEVICE_PRIVATE
>  	default n
>  	help
>  	  Say Y here if you want to enable experimental support for

Ben, I heard you might have a patch like this in your tree, but I
don't think I could find your tree?? 

Do you have any nouveau/Kconfig patches that might conflict? Thanks

Does this fix the randconfigs failures that have been reported?

> diff --git a/mm/Kconfig b/mm/Kconfig
> index 406fa45e9ecc..4dbd718c8cf4 100644
> +++ b/mm/Kconfig
> @@ -677,13 +677,13 @@ config ARCH_HAS_HMM_MIRROR
>  
>  config ARCH_HAS_HMM
>  	bool
> -	default y
>  	depends on (X86_64 || PPC64)
>  	depends on ZONE_DEVICE
>  	depends on MMU && 64BIT
>  	depends on MEMORY_HOTPLUG
>  	depends on MEMORY_HOTREMOVE
>  	depends on SPARSEMEM_VMEMMAP
> +	default y

What is the reason we have this ARCH thing anyhow? Does hmm have arch
dependencies someplace?

Thanks
Jason