Moving Dom0less to common, Was: [PATCH 0/5] Fine granular configuration

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

Adding hyperlaunch and x86 maintainers.


Hi Luca,

This patch series is very timely. You might not have realized but we
were just discussing with the hyperlaunch guys to move dom0less code to
common.

Your series is a great step in the right direction. However, we don't
want to move the dom0less code twice because it would make 'git blame'
very hard to use.

I wonder if I could ask you to move the code to xen/common/ instead. I
am not asking you to make it buildable on x86, as that would take more
work and also something along the lines of this patch series from
Christopher:
https://patchew.org/Xen/20230701071835.41599-1-christopher.w.clark@xxxxxxxxx/

The new code could be protected by CONFIG_DOM0LESS, and CONFIG_DOM0LESS
could only be selectable on ARM, not on x86.

Would you be OK with doing some extra work to move it to xen/common
instead?

Would the x86 maintainers be OK with it too? Of course further changes
will be needed to make it useable on x86, but looking at the series from
Christopher, the two sets of internal interfaces (dom0less/ARM and
hyperlaunch/x86) are very much aligned and similar already.

Cheers,

Stefano


On Tue, 8 Aug 2023, Luca Fancellu wrote:
> This serie aims to add more modularity to some feature that can be excluded
> without issues from the build.
> 
> The first patch is already reviewed.
> 
> Luca Fancellu (5):
>   arm/gicv2: make GICv2 driver and vGICv2 optional
>   xen/arm: Add asm/domain.h include to kernel.h
>   arm/dom0less: put dom0less feature code in a separate module
>   xen/arm: Move static memory build code in separate modules
>   arm/dom0less: introduce Kconfig for dom0less feature
> 
>  xen/arch/arm/Kconfig                      |   28 +
>  xen/arch/arm/Makefile                     |    7 +-
>  xen/arch/arm/bootfdt.c                    |  161 +-
>  xen/arch/arm/dom0less-build.c             | 1086 ++++++
>  xen/arch/arm/domain_build.c               | 4096 ++++++---------------
>  xen/arch/arm/efi/efi-boot.h               |    4 +
>  xen/arch/arm/gic-v3.c                     |    4 +
>  xen/arch/arm/include/asm/dom0less-build.h |   35 +
>  xen/arch/arm/include/asm/domain_build.h   |   33 +
>  xen/arch/arm/include/asm/kernel.h         |    1 +
>  xen/arch/arm/include/asm/setup.h          |    1 -
>  xen/arch/arm/include/asm/static-memory.h  |   50 +
>  xen/arch/arm/include/asm/static-shmem.h   |   72 +
>  xen/arch/arm/setup.c                      |   58 +-
>  xen/arch/arm/static-memory.c              |  294 ++
>  xen/arch/arm/static-shmem.c               |  515 +++
>  xen/arch/arm/vgic.c                       |    2 +
>  xen/arch/arm/vgic/Makefile                |    4 +-
>  18 files changed, 3357 insertions(+), 3094 deletions(-)
>  create mode 100644 xen/arch/arm/dom0less-build.c
>  create mode 100644 xen/arch/arm/include/asm/dom0less-build.h
>  create mode 100644 xen/arch/arm/include/asm/static-memory.h
>  create mode 100644 xen/arch/arm/include/asm/static-shmem.h
>  create mode 100644 xen/arch/arm/static-memory.c
>  create mode 100644 xen/arch/arm/static-shmem.c
> 
> -- 
> 2.34.1
>