Re: [PATCH] iommu: Change kconfig around IOMMU_SVA

[Jason Gunthorpe]

On Tue, Nov 28, 2023 at 10:16:35AM +0800, Tina Zhang wrote:
> From: Jason Gunthorpe <jgg@xxxxxxxxxx>
> 
> Linus suggested that the kconfig here is confusing:
> 
> https://lore.kernel.org/all/CAHk-=wgUiAtiszwseM1p2fCJ+sC4XWQ+YN4TanFhUgvUqjr9Xw@xxxxxxxxxxxxxx/
> 
> Let's break it into three kconfigs controlling distinct things:
> 
>  - CONFIG_IOMMU_MM_DATA controls if the mm_struct has the additional
>    fields for the IOMMU. Currently only PASID, but later patches store
>    a struct iommu_mm_data *
> 
>  - CONFIG_ARCH_HAS_CPU_PASID controls if the arch needs the scheduling bit
>    for keeping track of the ENQCMD instruction. x86 will select this if
>    IOMMU_SVA is enabled
> 
>  - IOMMU_SVA controls if the IOMMU core compiles in the SVA support code
>    for iommu driver use and the IOMMU exported API
> 
> This way ARM will not enable CONFIG_ARCH_HAS_CPU_PASID
> 
> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Signed-off-by: Tina Zhang <tina.zhang@xxxxxxxxx>
> ---
>  arch/Kconfig             | 5 +++++
>  arch/x86/Kconfig         | 1 +
>  arch/x86/kernel/traps.c  | 2 +-
>  drivers/iommu/Kconfig    | 1 +
>  include/linux/iommu.h    | 2 +-
>  include/linux/mm_types.h | 2 +-
>  include/linux/sched.h    | 2 +-
>  kernel/fork.c            | 2 +-
>  mm/Kconfig               | 3 +++
>  mm/init-mm.c             | 2 +-
>  10 files changed, 16 insertions(+), 6 deletions(-)

Try again, you need to cc the mm list and the x86 list

Jason